diff --git a/packages/cxx-gen-lsp/src/MetaModel.ts b/packages/cxx-gen-lsp/src/MetaModel.ts
index d8bb8730..e6954d50 100644
--- a/packages/cxx-gen-lsp/src/MetaModel.ts
+++ b/packages/cxx-gen-lsp/src/MetaModel.ts
@@ -199,7 +199,7 @@ export function toCppType(type: Type): string {
       return `std::tuple<${type.items.map(toCppType).join(", ")}>`;
 
     case "or":
-      return `std::variant<std::monostate, ${type.items.map(toCppType).join(", ")}>`;
+      return `std::variant<${type.items.map(toCppType).join(", ")}>`;
 
     case "and":
       return `std::tuple<${type.items.map(toCppType).join(", ")}>`;
diff --git a/packages/cxx-gen-lsp/src/gen_fwd_h.ts b/packages/cxx-gen-lsp/src/gen_fwd_h.ts
index d63c6b42..0a744323 100644
--- a/packages/cxx-gen-lsp/src/gen_fwd_h.ts
+++ b/packages/cxx-gen-lsp/src/gen_fwd_h.ts
@@ -31,8 +31,10 @@ using Pattern = std::string;
 
 class LSPObject {
   public:
+    LSPObject() = default;
     explicit LSPObject(json& repr): repr_(&repr) {}
 
+    [[nodiscard]] explicit operator bool() const { return repr_ != nullptr; }
     [[nodiscard]] operator const json&() const { return *repr_; }
     [[nodiscard]] auto get() const -> json& { return *repr_; }
 
@@ -45,7 +47,7 @@ class Vector final : public LSPObject {
 public:
   using LSPObject::LSPObject;
 
-  [[nodiscard]] explicit operator bool() const { return repr_->is_array(); }
+  [[nodiscard]] explicit operator bool() const { return repr_ && repr_->is_array(); }
   [[nodiscard]] auto size() const -> std::size_t { return repr_->size(); }
   [[nodiscard]] auto empty() const -> bool { return repr_->empty(); }
   [[nodiscard]] auto at(int index) const -> const T& { return repr_->at(index); }
@@ -71,11 +73,6 @@ auto try_emplace(std::variant<Ts...>& result, json& value) -> bool {
   return (details::TryEmplace<Ts>{}(result, value) || ...);
 }
 
-template <>
-struct TryEmplace<std::monostate> {
-  auto operator()(auto&, const json&) const -> bool { return false; }
-};
-
 template <>
 struct TryEmplace<std::nullptr_t> {
   auto operator()(auto& result, json& value) const -> bool {
@@ -169,7 +166,7 @@ class Vector<std::variant<Ts...>> final : public LSPObject {
   public:
   using LSPObject::LSPObject;
 
-  [[nodiscard]] explicit operator bool() const { return repr_->is_array(); }
+  [[nodiscard]] explicit operator bool() const { return repr_ && repr_->is_array(); }
   [[nodiscard]] auto size() const -> std::size_t { return repr_->size(); }
   [[nodiscard]] auto empty() const -> bool { return repr_->empty(); }
   [[nodiscard]] auto at(int index) const -> std::variant<Ts...> {
@@ -184,7 +181,7 @@ class Map final : public LSPObject {
 public:
   using LSPObject::LSPObject;
 
-  [[nodiscard]] explicit operator bool() const { return repr_->is_object(); }
+  [[nodiscard]] explicit operator bool() const { return repr_ && repr_->is_object(); }
   [[nodiscard]] auto size() const -> std::size_t { return repr_->size(); }
   [[nodiscard]] auto empty() const -> bool { return repr_->empty(); }
   [[nodiscard]] auto at(const Key& key) const -> const Value& { return repr_->at(key); }
@@ -195,7 +192,7 @@ class Map<Key, std::variant<Ts...>> final : public LSPObject {
   public:
   using LSPObject::LSPObject;
 
-  [[nodiscard]] explicit operator bool() const { return repr_->is_object(); }
+  [[nodiscard]] explicit operator bool() const { return repr_ && repr_->is_object(); }
   [[nodiscard]] auto size() const -> std::size_t { return repr_->size(); }
   [[nodiscard]] auto empty() const -> bool { return repr_->empty(); }
 
diff --git a/packages/cxx-gen-lsp/src/gen_types_cc.ts b/packages/cxx-gen-lsp/src/gen_types_cc.ts
index 1edd7812..83bbdebc 100644
--- a/packages/cxx-gen-lsp/src/gen_types_cc.ts
+++ b/packages/cxx-gen-lsp/src/gen_types_cc.ts
@@ -188,16 +188,17 @@ class TypeGenerator {
       }
 
       case "array":
-        this.emit(`assert(value.is_array());`);
+        this.emit(`if (value.is_null()) value = json::array();`);
         this.emit(`return ${propertyType}(value);`);
         return;
 
       case "map":
-        this.emit(`assert(value.is_object());`);
+        this.emit(`if (value.is_null()) value = json::object();`);
         this.emit(`return ${propertyType}(value);`);
         return;
 
       case "stringLiteral":
+        this.emit(`if (value.is_null()) value = "${property.type.value}";`);
         this.emit(`assert(value.is_string());`);
         this.emit(`return value.get<std::string>();`);
         return;
@@ -222,36 +223,43 @@ class TypeGenerator {
         throw new Error(`Unexpected null type`);
 
       case "string":
+        this.emit(`if (value.is_null()) value = "";`);
         this.emit(`assert(value.is_string());`);
         this.emit(`return value.get<std::string>();`);
         return true;
 
       case "integer":
+        this.emit(`if (value.is_null()) value = 0;`);
         this.emit(`assert(value.is_number_integer());`);
         this.emit(`return value.get<int>();`);
         return true;
 
       case "uinteger":
+        this.emit(`if (value.is_null()) value = 0;`);
         this.emit(`assert(value.is_number_integer());`);
         this.emit(`return value.get<long>();`);
         return true;
 
       case "decimal":
+        this.emit(`if (value.is_null()) value = 0.0;`);
         this.emit(`assert(value.is_number());`);
         this.emit(`return value.get<double>();`);
         return true;
 
       case "boolean":
+        this.emit(`if (value.is_null()) value = false;`);
         this.emit(`assert(value.is_boolean());`);
         this.emit(`return value.get<bool>();`);
         return true;
 
       case "DocumentUri":
+        this.emit(`if (value.is_null()) value = "";`);
         this.emit(`assert(value.is_string());`);
         this.emit(`return value.get<std::string>();`);
         return true;
 
       case "URI":
+        this.emit(`if (value.is_null()) value = "";`);
         this.emit(`assert(value.is_string());`);
         this.emit(`return value.get<std::string>();`);
         return true;
@@ -347,7 +355,7 @@ class TypeGenerator {
 
     switch (property.type.kind) {
       case "base":
-        this.emit(`repr_->emplace("${property.name}", std::move(${value}));`);
+        this.emit(`(*repr_)["${property.name}"] = std::move(${value});`);
         return;
 
       case "reference":
@@ -380,7 +388,7 @@ class TypeGenerator {
 
       if (enumeration.type.name !== "string") {
         const enumBaseType = toCppType(enumeration.type);
-        this.emit(`repr_->emplace("${property.name}", static_cast<${enumBaseType}>(${value}));`);
+        this.emit(`(*repr_)["${property.name}"] = static_cast<${enumBaseType}>(${value});`);
         return true;
       }
 
@@ -389,7 +397,7 @@ class TypeGenerator {
     }
 
     if (this.structByName.has(property.type.name)) {
-      this.emit(`repr_->emplace("${property.name}", ${value});`);
+      this.emit(`(*repr_)["${property.name}"] = ${value};`);
       return true;
     }
 
@@ -407,15 +415,9 @@ class TypeGenerator {
   }): boolean {
     if (property.type.kind !== "or") return false;
 
-    this.emit();
-    this.emit("// or type");
     this.emit();
     this.emit(`struct {`);
     this.emit(`json* repr_;`);
-    this.emit();
-    this.emit(`void operator()(std::monostate) {`);
-    this.emit(`lsp_runtime_error("monostate is not a valid a property value");`);
-    this.emit(`}`);
 
     property.type.items.forEach((item) => {
       const itemType = this.getPropertyType({ type: item });
diff --git a/src/lsp/cxx/lsp/fwd.h b/src/lsp/cxx/lsp/fwd.h
index ab31c7af..62b047a8 100644
--- a/src/lsp/cxx/lsp/fwd.h
+++ b/src/lsp/cxx/lsp/fwd.h
@@ -463,8 +463,10 @@ using Pattern = std::string;
 
 class LSPObject {
  public:
+  LSPObject() = default;
   explicit LSPObject(json& repr) : repr_(&repr) {}
 
+  [[nodiscard]] explicit operator bool() const { return repr_ != nullptr; }
   [[nodiscard]] operator const json&() const { return *repr_; }
   [[nodiscard]] auto get() const -> json& { return *repr_; }
 
@@ -477,7 +479,9 @@ class Vector final : public LSPObject {
  public:
   using LSPObject::LSPObject;
 
-  [[nodiscard]] explicit operator bool() const { return repr_->is_array(); }
+  [[nodiscard]] explicit operator bool() const {
+    return repr_ && repr_->is_array();
+  }
   [[nodiscard]] auto size() const -> std::size_t { return repr_->size(); }
   [[nodiscard]] auto empty() const -> bool { return repr_->empty(); }
   [[nodiscard]] auto at(int index) const -> const T& {
@@ -505,11 +509,6 @@ auto try_emplace(std::variant<Ts...>& result, json& value) -> bool {
   return (details::TryEmplace<Ts>{}(result, value) || ...);
 }
 
-template <>
-struct TryEmplace<std::monostate> {
-  auto operator()(auto&, const json&) const -> bool { return false; }
-};
-
 template <>
 struct TryEmplace<std::nullptr_t> {
   auto operator()(auto& result, json& value) const -> bool {
@@ -603,7 +602,9 @@ class Vector<std::variant<Ts...>> final : public LSPObject {
  public:
   using LSPObject::LSPObject;
 
-  [[nodiscard]] explicit operator bool() const { return repr_->is_array(); }
+  [[nodiscard]] explicit operator bool() const {
+    return repr_ && repr_->is_array();
+  }
   [[nodiscard]] auto size() const -> std::size_t { return repr_->size(); }
   [[nodiscard]] auto empty() const -> bool { return repr_->empty(); }
   [[nodiscard]] auto at(int index) const -> std::variant<Ts...> {
@@ -618,7 +619,9 @@ class Map final : public LSPObject {
  public:
   using LSPObject::LSPObject;
 
-  [[nodiscard]] explicit operator bool() const { return repr_->is_object(); }
+  [[nodiscard]] explicit operator bool() const {
+    return repr_ && repr_->is_object();
+  }
   [[nodiscard]] auto size() const -> std::size_t { return repr_->size(); }
   [[nodiscard]] auto empty() const -> bool { return repr_->empty(); }
   [[nodiscard]] auto at(const Key& key) const -> const Value& {
@@ -631,7 +634,9 @@ class Map<Key, std::variant<Ts...>> final : public LSPObject {
  public:
   using LSPObject::LSPObject;
 
-  [[nodiscard]] explicit operator bool() const { return repr_->is_object(); }
+  [[nodiscard]] explicit operator bool() const {
+    return repr_ && repr_->is_object();
+  }
   [[nodiscard]] auto size() const -> std::size_t { return repr_->size(); }
   [[nodiscard]] auto empty() const -> bool { return repr_->empty(); }
 
@@ -645,53 +650,50 @@ class Map<Key, std::variant<Ts...>> final : public LSPObject {
 using RegularExpressionEngineKind = std::string;
 
 using NotebookDocumentFilter =
-    std::variant<std::monostate, NotebookDocumentFilterNotebookType,
+    std::variant<NotebookDocumentFilterNotebookType,
                  NotebookDocumentFilterScheme, NotebookDocumentFilterPattern>;
 
 using TextDocumentFilter =
-    std::variant<std::monostate, TextDocumentFilterLanguage,
-                 TextDocumentFilterScheme, TextDocumentFilterPattern>;
+    std::variant<TextDocumentFilterLanguage, TextDocumentFilterScheme,
+                 TextDocumentFilterPattern>;
 
-using GlobPattern = std::variant<std::monostate, Pattern, RelativePattern>;
+using GlobPattern = std::variant<Pattern, RelativePattern>;
 
-using DocumentFilter = std::variant<std::monostate, TextDocumentFilter,
-                                    NotebookCellTextDocumentFilter>;
+using DocumentFilter =
+    std::variant<TextDocumentFilter, NotebookCellTextDocumentFilter>;
 
-using MarkedString =
-    std::variant<std::monostate, std::string, MarkedStringWithLanguage>;
+using MarkedString = std::variant<std::string, MarkedStringWithLanguage>;
 
 using TextDocumentContentChangeEvent =
-    std::variant<std::monostate, TextDocumentContentChangePartial,
+    std::variant<TextDocumentContentChangePartial,
                  TextDocumentContentChangeWholeDocument>;
 
 using WorkspaceDocumentDiagnosticReport =
-    std::variant<std::monostate, WorkspaceFullDocumentDiagnosticReport,
+    std::variant<WorkspaceFullDocumentDiagnosticReport,
                  WorkspaceUnchangedDocumentDiagnosticReport>;
 
 using ChangeAnnotationIdentifier = std::string;
 
-using ProgressToken = std::variant<std::monostate, int, std::string>;
+using ProgressToken = std::variant<int, std::string>;
 
 using DocumentSelector = Vector<DocumentFilter>;
 
 using PrepareRenameResult =
-    std::variant<std::monostate, Range, PrepareRenamePlaceholder,
-                 PrepareRenameDefaultBehavior>;
+    std::variant<Range, PrepareRenamePlaceholder, PrepareRenameDefaultBehavior>;
 
 using DocumentDiagnosticReport =
-    std::variant<std::monostate, RelatedFullDocumentDiagnosticReport,
+    std::variant<RelatedFullDocumentDiagnosticReport,
                  RelatedUnchangedDocumentDiagnosticReport>;
 
-using InlineValue =
-    std::variant<std::monostate, InlineValueText, InlineValueVariableLookup,
-                 InlineValueEvaluatableExpression>;
+using InlineValue = std::variant<InlineValueText, InlineValueVariableLookup,
+                                 InlineValueEvaluatableExpression>;
 
 using DeclarationLink = LocationLink;
 
-using Declaration = std::variant<std::monostate, Location, Vector<Location>>;
+using Declaration = std::variant<Location, Vector<Location>>;
 
 using DefinitionLink = LocationLink;
 
-using Definition = std::variant<std::monostate, Location, Vector<Location>>;
+using Definition = std::variant<Location, Vector<Location>>;
 
 }  // namespace cxx::lsp
diff --git a/src/lsp/cxx/lsp/types.cc b/src/lsp/cxx/lsp/types.cc
index fae76a2b..09ae6c39 100644
--- a/src/lsp/cxx/lsp/types.cc
+++ b/src/lsp/cxx/lsp/types.cc
@@ -69,13 +69,13 @@ auto ImplementationParams::partialResultToken() const
 
 auto ImplementationParams::textDocument(TextDocumentIdentifier textDocument)
     -> ImplementationParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto ImplementationParams::position(Position position)
     -> ImplementationParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -110,6 +110,7 @@ Location::operator bool() const {
 auto Location::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -121,12 +122,12 @@ auto Location::range() const -> Range {
 }
 
 auto Location::uri(std::string uri) -> Location& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto Location::range(Range range) -> Location& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -137,10 +138,10 @@ ImplementationRegistrationOptions::operator bool() const {
 }
 
 auto ImplementationRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -153,6 +154,7 @@ auto ImplementationRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -163,22 +165,17 @@ auto ImplementationRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto ImplementationRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> ImplementationRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> ImplementationRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "ImplementationRegistrationOptions::documentSelector: not implement "
@@ -186,7 +183,7 @@ auto ImplementationRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -202,7 +199,7 @@ auto ImplementationRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -212,7 +209,7 @@ auto ImplementationRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -263,13 +260,13 @@ auto TypeDefinitionParams::partialResultToken() const
 
 auto TypeDefinitionParams::textDocument(TextDocumentIdentifier textDocument)
     -> TypeDefinitionParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto TypeDefinitionParams::position(Position position)
     -> TypeDefinitionParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -301,10 +298,10 @@ TypeDefinitionRegistrationOptions::operator bool() const {
 }
 
 auto TypeDefinitionRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -317,6 +314,7 @@ auto TypeDefinitionRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -327,22 +325,17 @@ auto TypeDefinitionRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TypeDefinitionRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> TypeDefinitionRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> TypeDefinitionRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "TypeDefinitionRegistrationOptions::documentSelector: not implement "
@@ -350,7 +343,7 @@ auto TypeDefinitionRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -366,7 +359,7 @@ auto TypeDefinitionRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -376,7 +369,7 @@ auto TypeDefinitionRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -390,6 +383,7 @@ WorkspaceFolder::operator bool() const {
 auto WorkspaceFolder::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -397,17 +391,18 @@ auto WorkspaceFolder::uri() const -> std::string {
 auto WorkspaceFolder::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto WorkspaceFolder::uri(std::string uri) -> WorkspaceFolder& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto WorkspaceFolder::name(std::string name) -> WorkspaceFolder& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
@@ -426,7 +421,7 @@ auto DidChangeWorkspaceFoldersParams::event() const
 
 auto DidChangeWorkspaceFoldersParams::event(WorkspaceFoldersChangeEvent event)
     -> DidChangeWorkspaceFoldersParams& {
-  repr_->emplace("event", event);
+  (*repr_)["event"] = event;
   return *this;
 }
 
@@ -439,7 +434,7 @@ ConfigurationParams::operator bool() const {
 auto ConfigurationParams::items() const -> Vector<ConfigurationItem> {
   auto& value = (*repr_)["items"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<ConfigurationItem>(value);
 }
 
@@ -489,7 +484,7 @@ auto DocumentColorParams::partialResultToken() const
 
 auto DocumentColorParams::textDocument(TextDocumentIdentifier textDocument)
     -> DocumentColorParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -534,12 +529,12 @@ auto ColorInformation::color() const -> Color {
 }
 
 auto ColorInformation::range(Range range) -> ColorInformation& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto ColorInformation::color(Color color) -> ColorInformation& {
-  repr_->emplace("color", color);
+  (*repr_)["color"] = color;
   return *this;
 }
 
@@ -550,10 +545,10 @@ DocumentColorRegistrationOptions::operator bool() const {
 }
 
 auto DocumentColorRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -566,6 +561,7 @@ auto DocumentColorRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -576,22 +572,17 @@ auto DocumentColorRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto DocumentColorRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DocumentColorRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DocumentColorRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DocumentColorRegistrationOptions::documentSelector: not implement "
@@ -599,7 +590,7 @@ auto DocumentColorRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -614,7 +605,7 @@ auto DocumentColorRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -624,7 +615,7 @@ auto DocumentColorRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -682,17 +673,17 @@ auto ColorPresentationParams::partialResultToken() const
 
 auto ColorPresentationParams::textDocument(TextDocumentIdentifier textDocument)
     -> ColorPresentationParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto ColorPresentationParams::color(Color color) -> ColorPresentationParams& {
-  repr_->emplace("color", color);
+  (*repr_)["color"] = color;
   return *this;
 }
 
 auto ColorPresentationParams::range(Range range) -> ColorPresentationParams& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -728,6 +719,7 @@ ColorPresentation::operator bool() const {
 auto ColorPresentation::label() const -> std::string {
   auto& value = (*repr_)["label"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -746,12 +738,12 @@ auto ColorPresentation::additionalTextEdits() const
 
   auto& value = (*repr_)["additionalTextEdits"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextEdit>(value);
 }
 
 auto ColorPresentation::label(std::string label) -> ColorPresentation& {
-  repr_->emplace("label", std::move(label));
+  (*repr_)["label"] = std::move(label);
   return *this;
 }
 
@@ -761,7 +753,7 @@ auto ColorPresentation::textEdit(std::optional<TextEdit> textEdit)
     repr_->erase("textEdit");
     return *this;
   }
-  repr_->emplace("textEdit", textEdit.value());
+  (*repr_)["textEdit"] = textEdit.value();
   return *this;
 }
 
@@ -786,6 +778,7 @@ auto WorkDoneProgressOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -796,7 +789,7 @@ auto WorkDoneProgressOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -807,10 +800,10 @@ TextDocumentRegistrationOptions::operator bool() const {
 }
 
 auto TextDocumentRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -818,17 +811,11 @@ auto TextDocumentRegistrationOptions::documentSelector() const
 }
 
 auto TextDocumentRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> TextDocumentRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> TextDocumentRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "TextDocumentRegistrationOptions::documentSelector: not implement "
@@ -836,7 +823,7 @@ auto TextDocumentRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -884,7 +871,7 @@ auto FoldingRangeParams::partialResultToken() const
 
 auto FoldingRangeParams::textDocument(TextDocumentIdentifier textDocument)
     -> FoldingRangeParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -919,6 +906,7 @@ FoldingRange::operator bool() const {
 auto FoldingRange::startLine() const -> long {
   auto& value = (*repr_)["startLine"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -928,6 +916,7 @@ auto FoldingRange::startCharacter() const -> std::optional<long> {
 
   auto& value = (*repr_)["startCharacter"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -935,6 +924,7 @@ auto FoldingRange::startCharacter() const -> std::optional<long> {
 auto FoldingRange::endLine() const -> long {
   auto& value = (*repr_)["endLine"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -944,6 +934,7 @@ auto FoldingRange::endCharacter() const -> std::optional<long> {
 
   auto& value = (*repr_)["endCharacter"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -961,12 +952,13 @@ auto FoldingRange::collapsedText() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["collapsedText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto FoldingRange::startLine(long startLine) -> FoldingRange& {
-  repr_->emplace("startLine", std::move(startLine));
+  (*repr_)["startLine"] = std::move(startLine);
   return *this;
 }
 
@@ -976,12 +968,12 @@ auto FoldingRange::startCharacter(std::optional<long> startCharacter)
     repr_->erase("startCharacter");
     return *this;
   }
-  repr_->emplace("startCharacter", std::move(startCharacter.value()));
+  (*repr_)["startCharacter"] = std::move(startCharacter.value());
   return *this;
 }
 
 auto FoldingRange::endLine(long endLine) -> FoldingRange& {
-  repr_->emplace("endLine", std::move(endLine));
+  (*repr_)["endLine"] = std::move(endLine);
   return *this;
 }
 
@@ -991,7 +983,7 @@ auto FoldingRange::endCharacter(std::optional<long> endCharacter)
     repr_->erase("endCharacter");
     return *this;
   }
-  repr_->emplace("endCharacter", std::move(endCharacter.value()));
+  (*repr_)["endCharacter"] = std::move(endCharacter.value());
   return *this;
 }
 
@@ -1010,7 +1002,7 @@ auto FoldingRange::collapsedText(std::optional<std::string> collapsedText)
     repr_->erase("collapsedText");
     return *this;
   }
-  repr_->emplace("collapsedText", std::move(collapsedText.value()));
+  (*repr_)["collapsedText"] = std::move(collapsedText.value());
   return *this;
 }
 
@@ -1021,10 +1013,10 @@ FoldingRangeRegistrationOptions::operator bool() const {
 }
 
 auto FoldingRangeRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -1037,6 +1029,7 @@ auto FoldingRangeRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -1046,22 +1039,17 @@ auto FoldingRangeRegistrationOptions::id() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto FoldingRangeRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> FoldingRangeRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> FoldingRangeRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "FoldingRangeRegistrationOptions::documentSelector: not implement "
@@ -1069,7 +1057,7 @@ auto FoldingRangeRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -1084,7 +1072,7 @@ auto FoldingRangeRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -1094,7 +1082,7 @@ auto FoldingRangeRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -1144,12 +1132,12 @@ auto DeclarationParams::partialResultToken() const
 
 auto DeclarationParams::textDocument(TextDocumentIdentifier textDocument)
     -> DeclarationParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto DeclarationParams::position(Position position) -> DeclarationParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -1185,15 +1173,16 @@ auto DeclarationRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto DeclarationRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -1205,6 +1194,7 @@ auto DeclarationRegistrationOptions::id() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -1215,22 +1205,16 @@ auto DeclarationRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
 auto DeclarationRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DeclarationRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DeclarationRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DeclarationRegistrationOptions::documentSelector: not implement "
@@ -1238,7 +1222,7 @@ auto DeclarationRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -1253,7 +1237,7 @@ auto DeclarationRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -1273,7 +1257,7 @@ auto SelectionRangeParams::textDocument() const -> TextDocumentIdentifier {
 auto SelectionRangeParams::positions() const -> Vector<Position> {
   auto& value = (*repr_)["positions"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Position>(value);
 }
 
@@ -1305,7 +1289,7 @@ auto SelectionRangeParams::partialResultToken() const
 
 auto SelectionRangeParams::textDocument(TextDocumentIdentifier textDocument)
     -> SelectionRangeParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -1357,7 +1341,7 @@ auto SelectionRange::parent() const -> std::optional<SelectionRange> {
 }
 
 auto SelectionRange::range(Range range) -> SelectionRange& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -1367,7 +1351,7 @@ auto SelectionRange::parent(std::optional<SelectionRange> parent)
     repr_->erase("parent");
     return *this;
   }
-  repr_->emplace("parent", parent.value());
+  (*repr_)["parent"] = parent.value();
   return *this;
 }
 
@@ -1383,15 +1367,16 @@ auto SelectionRangeRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto SelectionRangeRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -1404,6 +1389,7 @@ auto SelectionRangeRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -1415,22 +1401,16 @@ auto SelectionRangeRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
 auto SelectionRangeRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> SelectionRangeRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> SelectionRangeRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "SelectionRangeRegistrationOptions::documentSelector: not implement "
@@ -1438,7 +1418,7 @@ auto SelectionRangeRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -1453,7 +1433,7 @@ auto SelectionRangeRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -1536,13 +1516,13 @@ auto CallHierarchyPrepareParams::workDoneToken() const
 
 auto CallHierarchyPrepareParams::textDocument(
     TextDocumentIdentifier textDocument) -> CallHierarchyPrepareParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto CallHierarchyPrepareParams::position(Position position)
     -> CallHierarchyPrepareParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -1570,6 +1550,7 @@ CallHierarchyItem::operator bool() const {
 auto CallHierarchyItem::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -1585,7 +1566,7 @@ auto CallHierarchyItem::tags() const -> std::optional<Vector<SymbolTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SymbolTag>(value);
 }
 
@@ -1594,6 +1575,7 @@ auto CallHierarchyItem::detail() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["detail"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -1601,6 +1583,7 @@ auto CallHierarchyItem::detail() const -> std::optional<std::string> {
 auto CallHierarchyItem::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -1627,12 +1610,12 @@ auto CallHierarchyItem::data() const -> std::optional<LSPAny> {
 }
 
 auto CallHierarchyItem::name(std::string name) -> CallHierarchyItem& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
 auto CallHierarchyItem::kind(SymbolKind kind) -> CallHierarchyItem& {
-  repr_->emplace("kind", static_cast<long>(kind));
+  (*repr_)["kind"] = static_cast<long>(kind);
   return *this;
 }
 
@@ -1652,23 +1635,23 @@ auto CallHierarchyItem::detail(std::optional<std::string> detail)
     repr_->erase("detail");
     return *this;
   }
-  repr_->emplace("detail", std::move(detail.value()));
+  (*repr_)["detail"] = std::move(detail.value());
   return *this;
 }
 
 auto CallHierarchyItem::uri(std::string uri) -> CallHierarchyItem& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto CallHierarchyItem::range(Range range) -> CallHierarchyItem& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto CallHierarchyItem::selectionRange(Range selectionRange)
     -> CallHierarchyItem& {
-  repr_->emplace("selectionRange", selectionRange);
+  (*repr_)["selectionRange"] = selectionRange;
   return *this;
 }
 
@@ -1688,10 +1671,10 @@ CallHierarchyRegistrationOptions::operator bool() const {
 }
 
 auto CallHierarchyRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -1704,6 +1687,7 @@ auto CallHierarchyRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -1714,22 +1698,17 @@ auto CallHierarchyRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto CallHierarchyRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> CallHierarchyRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> CallHierarchyRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "CallHierarchyRegistrationOptions::documentSelector: not implement "
@@ -1737,7 +1716,7 @@ auto CallHierarchyRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -1752,7 +1731,7 @@ auto CallHierarchyRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -1762,7 +1741,7 @@ auto CallHierarchyRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -1806,7 +1785,7 @@ auto CallHierarchyIncomingCallsParams::partialResultToken() const
 
 auto CallHierarchyIncomingCallsParams::item(CallHierarchyItem item)
     -> CallHierarchyIncomingCallsParams& {
-  repr_->emplace("item", item);
+  (*repr_)["item"] = item;
   return *this;
 }
 
@@ -1851,13 +1830,13 @@ auto CallHierarchyIncomingCall::from() const -> CallHierarchyItem {
 auto CallHierarchyIncomingCall::fromRanges() const -> Vector<Range> {
   auto& value = (*repr_)["fromRanges"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Range>(value);
 }
 
 auto CallHierarchyIncomingCall::from(CallHierarchyItem from)
     -> CallHierarchyIncomingCall& {
-  repr_->emplace("from", from);
+  (*repr_)["from"] = from;
   return *this;
 }
 
@@ -1907,7 +1886,7 @@ auto CallHierarchyOutgoingCallsParams::partialResultToken() const
 
 auto CallHierarchyOutgoingCallsParams::item(CallHierarchyItem item)
     -> CallHierarchyOutgoingCallsParams& {
-  repr_->emplace("item", item);
+  (*repr_)["item"] = item;
   return *this;
 }
 
@@ -1952,13 +1931,13 @@ auto CallHierarchyOutgoingCall::to() const -> CallHierarchyItem {
 auto CallHierarchyOutgoingCall::fromRanges() const -> Vector<Range> {
   auto& value = (*repr_)["fromRanges"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Range>(value);
 }
 
 auto CallHierarchyOutgoingCall::to(CallHierarchyItem to)
     -> CallHierarchyOutgoingCall& {
-  repr_->emplace("to", to);
+  (*repr_)["to"] = to;
   return *this;
 }
 
@@ -2008,7 +1987,7 @@ auto SemanticTokensParams::partialResultToken() const
 
 auto SemanticTokensParams::textDocument(TextDocumentIdentifier textDocument)
     -> SemanticTokensParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -2044,6 +2023,7 @@ auto SemanticTokens::resultId() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["resultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -2051,7 +2031,7 @@ auto SemanticTokens::resultId() const -> std::optional<std::string> {
 auto SemanticTokens::data() const -> Vector<long> {
   auto& value = (*repr_)["data"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<long>(value);
 }
 
@@ -2061,7 +2041,7 @@ auto SemanticTokens::resultId(std::optional<std::string> resultId)
     repr_->erase("resultId");
     return *this;
   }
-  repr_->emplace("resultId", std::move(resultId.value()));
+  (*repr_)["resultId"] = std::move(resultId.value());
   return *this;
 }
 
@@ -2079,7 +2059,7 @@ SemanticTokensPartialResult::operator bool() const {
 auto SemanticTokensPartialResult::data() const -> Vector<long> {
   auto& value = (*repr_)["data"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<long>(value);
 }
 
@@ -2097,10 +2077,10 @@ SemanticTokensRegistrationOptions::operator bool() const {
 }
 
 auto SemanticTokensRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -2114,25 +2094,25 @@ auto SemanticTokensRegistrationOptions::legend() const -> SemanticTokensLegend {
 }
 
 auto SemanticTokensRegistrationOptions::range() const
-    -> std::optional<std::variant<std::monostate, bool, json>> {
+    -> std::optional<std::variant<bool, json>> {
   if (!repr_->contains("range")) return std::nullopt;
 
   auto& value = (*repr_)["range"];
 
-  std::variant<std::monostate, bool, json> result;
+  std::variant<bool, json> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto SemanticTokensRegistrationOptions::full() const -> std::optional<
-    std::variant<std::monostate, bool, SemanticTokensFullDelta>> {
+auto SemanticTokensRegistrationOptions::full() const
+    -> std::optional<std::variant<bool, SemanticTokensFullDelta>> {
   if (!repr_->contains("full")) return std::nullopt;
 
   auto& value = (*repr_)["full"];
 
-  std::variant<std::monostate, bool, SemanticTokensFullDelta> result;
+  std::variant<bool, SemanticTokensFullDelta> result;
 
   details::try_emplace(result, value);
 
@@ -2145,6 +2125,7 @@ auto SemanticTokensRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -2155,22 +2136,17 @@ auto SemanticTokensRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto SemanticTokensRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> SemanticTokensRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> SemanticTokensRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "SemanticTokensRegistrationOptions::documentSelector: not implement "
@@ -2178,7 +2154,7 @@ auto SemanticTokensRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -2189,28 +2165,22 @@ auto SemanticTokensRegistrationOptions::documentSelector(
 
 auto SemanticTokensRegistrationOptions::legend(SemanticTokensLegend legend)
     -> SemanticTokensRegistrationOptions& {
-  repr_->emplace("legend", legend);
+  (*repr_)["legend"] = legend;
   return *this;
 }
 
 auto SemanticTokensRegistrationOptions::range(
-    std::optional<std::variant<std::monostate, bool, json>> range)
+    std::optional<std::variant<bool, json>> range)
     -> SemanticTokensRegistrationOptions& {
   if (!range.has_value()) {
     repr_->erase("range");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(bool range) { repr_->emplace("range", std::move(range)); }
+    void operator()(bool range) { (*repr_)["range"] = std::move(range); }
 
     void operator()(json range) {
       lsp_runtime_error(
@@ -2224,27 +2194,19 @@ auto SemanticTokensRegistrationOptions::range(
 }
 
 auto SemanticTokensRegistrationOptions::full(
-    std::optional<std::variant<std::monostate, bool, SemanticTokensFullDelta>>
-        full) -> SemanticTokensRegistrationOptions& {
+    std::optional<std::variant<bool, SemanticTokensFullDelta>> full)
+    -> SemanticTokensRegistrationOptions& {
   if (!full.has_value()) {
     repr_->erase("full");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(bool full) { repr_->emplace("full", std::move(full)); }
+    void operator()(bool full) { (*repr_)["full"] = std::move(full); }
 
-    void operator()(SemanticTokensFullDelta full) {
-      repr_->emplace("full", full);
-    }
+    void operator()(SemanticTokensFullDelta full) { (*repr_)["full"] = full; }
   } v{repr_};
 
   std::visit(v, full.value());
@@ -2259,7 +2221,7 @@ auto SemanticTokensRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -2269,7 +2231,7 @@ auto SemanticTokensRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -2289,6 +2251,7 @@ auto SemanticTokensDeltaParams::textDocument() const -> TextDocumentIdentifier {
 auto SemanticTokensDeltaParams::previousResultId() const -> std::string {
   auto& value = (*repr_)["previousResultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -2321,13 +2284,13 @@ auto SemanticTokensDeltaParams::partialResultToken() const
 
 auto SemanticTokensDeltaParams::textDocument(
     TextDocumentIdentifier textDocument) -> SemanticTokensDeltaParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto SemanticTokensDeltaParams::previousResultId(std::string previousResultId)
     -> SemanticTokensDeltaParams& {
-  repr_->emplace("previousResultId", std::move(previousResultId));
+  (*repr_)["previousResultId"] = std::move(previousResultId);
   return *this;
 }
 
@@ -2365,6 +2328,7 @@ auto SemanticTokensDelta::resultId() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["resultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -2372,7 +2336,7 @@ auto SemanticTokensDelta::resultId() const -> std::optional<std::string> {
 auto SemanticTokensDelta::edits() const -> Vector<SemanticTokensEdit> {
   auto& value = (*repr_)["edits"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SemanticTokensEdit>(value);
 }
 
@@ -2382,7 +2346,7 @@ auto SemanticTokensDelta::resultId(std::optional<std::string> resultId)
     repr_->erase("resultId");
     return *this;
   }
-  repr_->emplace("resultId", std::move(resultId.value()));
+  (*repr_)["resultId"] = std::move(resultId.value());
   return *this;
 }
 
@@ -2402,7 +2366,7 @@ auto SemanticTokensDeltaPartialResult::edits() const
     -> Vector<SemanticTokensEdit> {
   auto& value = (*repr_)["edits"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SemanticTokensEdit>(value);
 }
 
@@ -2460,13 +2424,13 @@ auto SemanticTokensRangeParams::partialResultToken() const
 
 auto SemanticTokensRangeParams::textDocument(
     TextDocumentIdentifier textDocument) -> SemanticTokensRangeParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto SemanticTokensRangeParams::range(Range range)
     -> SemanticTokensRangeParams& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -2502,6 +2466,7 @@ ShowDocumentParams::operator bool() const {
 auto ShowDocumentParams::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -2511,6 +2476,7 @@ auto ShowDocumentParams::external() const -> std::optional<bool> {
 
   auto& value = (*repr_)["external"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -2520,6 +2486,7 @@ auto ShowDocumentParams::takeFocus() const -> std::optional<bool> {
 
   auto& value = (*repr_)["takeFocus"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -2533,7 +2500,7 @@ auto ShowDocumentParams::selection() const -> std::optional<Range> {
 }
 
 auto ShowDocumentParams::uri(std::string uri) -> ShowDocumentParams& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -2543,7 +2510,7 @@ auto ShowDocumentParams::external(std::optional<bool> external)
     repr_->erase("external");
     return *this;
   }
-  repr_->emplace("external", std::move(external.value()));
+  (*repr_)["external"] = std::move(external.value());
   return *this;
 }
 
@@ -2553,7 +2520,7 @@ auto ShowDocumentParams::takeFocus(std::optional<bool> takeFocus)
     repr_->erase("takeFocus");
     return *this;
   }
-  repr_->emplace("takeFocus", std::move(takeFocus.value()));
+  (*repr_)["takeFocus"] = std::move(takeFocus.value());
   return *this;
 }
 
@@ -2563,7 +2530,7 @@ auto ShowDocumentParams::selection(std::optional<Range> selection)
     repr_->erase("selection");
     return *this;
   }
-  repr_->emplace("selection", selection.value());
+  (*repr_)["selection"] = selection.value();
   return *this;
 }
 
@@ -2576,12 +2543,13 @@ ShowDocumentResult::operator bool() const {
 auto ShowDocumentResult::success() const -> bool {
   auto& value = (*repr_)["success"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto ShowDocumentResult::success(bool success) -> ShowDocumentResult& {
-  repr_->emplace("success", std::move(success));
+  (*repr_)["success"] = std::move(success);
   return *this;
 }
 
@@ -2619,13 +2587,13 @@ auto LinkedEditingRangeParams::workDoneToken() const
 
 auto LinkedEditingRangeParams::textDocument(TextDocumentIdentifier textDocument)
     -> LinkedEditingRangeParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto LinkedEditingRangeParams::position(Position position)
     -> LinkedEditingRangeParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -2649,7 +2617,7 @@ LinkedEditingRanges::operator bool() const {
 auto LinkedEditingRanges::ranges() const -> Vector<Range> {
   auto& value = (*repr_)["ranges"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Range>(value);
 }
 
@@ -2658,6 +2626,7 @@ auto LinkedEditingRanges::wordPattern() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["wordPattern"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -2673,7 +2642,7 @@ auto LinkedEditingRanges::wordPattern(std::optional<std::string> wordPattern)
     repr_->erase("wordPattern");
     return *this;
   }
-  repr_->emplace("wordPattern", std::move(wordPattern.value()));
+  (*repr_)["wordPattern"] = std::move(wordPattern.value());
   return *this;
 }
 
@@ -2684,10 +2653,10 @@ LinkedEditingRangeRegistrationOptions::operator bool() const {
 }
 
 auto LinkedEditingRangeRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -2700,6 +2669,7 @@ auto LinkedEditingRangeRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -2710,22 +2680,17 @@ auto LinkedEditingRangeRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto LinkedEditingRangeRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> LinkedEditingRangeRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> LinkedEditingRangeRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "LinkedEditingRangeRegistrationOptions::documentSelector: not "
@@ -2733,7 +2698,7 @@ auto LinkedEditingRangeRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -2749,7 +2714,7 @@ auto LinkedEditingRangeRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -2759,7 +2724,7 @@ auto LinkedEditingRangeRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -2772,7 +2737,7 @@ CreateFilesParams::operator bool() const {
 auto CreateFilesParams::files() const -> Vector<FileCreate> {
   auto& value = (*repr_)["files"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<FileCreate>(value);
 }
 
@@ -2792,20 +2757,20 @@ auto WorkspaceEdit::changes() const
 
   auto& value = (*repr_)["changes"];
 
-  assert(value.is_object());
+  if (value.is_null()) value = json::object();
   return Map<std::string, Vector<TextEdit>>(value);
 }
 
-auto WorkspaceEdit::documentChanges() const
-    -> std::optional<Vector<std::variant<std::monostate, TextDocumentEdit,
-                                         CreateFile, RenameFile, DeleteFile>>> {
+auto WorkspaceEdit::documentChanges() const -> std::optional<Vector<
+    std::variant<TextDocumentEdit, CreateFile, RenameFile, DeleteFile>>> {
   if (!repr_->contains("documentChanges")) return std::nullopt;
 
   auto& value = (*repr_)["documentChanges"];
 
-  assert(value.is_array());
-  return Vector<std::variant<std::monostate, TextDocumentEdit, CreateFile,
-                             RenameFile, DeleteFile>>(value);
+  if (value.is_null()) value = json::array();
+  return Vector<
+      std::variant<TextDocumentEdit, CreateFile, RenameFile, DeleteFile>>(
+      value);
 }
 
 auto WorkspaceEdit::changeAnnotations() const
@@ -2814,7 +2779,7 @@ auto WorkspaceEdit::changeAnnotations() const
 
   auto& value = (*repr_)["changeAnnotations"];
 
-  assert(value.is_object());
+  if (value.is_null()) value = json::object();
   return Map<ChangeAnnotationIdentifier, ChangeAnnotation>(value);
 }
 
@@ -2830,8 +2795,8 @@ auto WorkspaceEdit::changes(
 }
 
 auto WorkspaceEdit::documentChanges(
-    std::optional<Vector<std::variant<std::monostate, TextDocumentEdit,
-                                      CreateFile, RenameFile, DeleteFile>>>
+    std::optional<Vector<
+        std::variant<TextDocumentEdit, CreateFile, RenameFile, DeleteFile>>>
         documentChanges) -> WorkspaceEdit& {
   if (!documentChanges.has_value()) {
     repr_->erase("documentChanges");
@@ -2862,7 +2827,7 @@ auto FileOperationRegistrationOptions::filters() const
     -> Vector<FileOperationFilter> {
   auto& value = (*repr_)["filters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<FileOperationFilter>(value);
 }
 
@@ -2882,7 +2847,7 @@ RenameFilesParams::operator bool() const {
 auto RenameFilesParams::files() const -> Vector<FileRename> {
   auto& value = (*repr_)["files"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<FileRename>(value);
 }
 
@@ -2900,7 +2865,7 @@ DeleteFilesParams::operator bool() const {
 auto DeleteFilesParams::files() const -> Vector<FileDelete> {
   auto& value = (*repr_)["files"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<FileDelete>(value);
 }
 
@@ -2954,12 +2919,12 @@ auto MonikerParams::partialResultToken() const -> std::optional<ProgressToken> {
 
 auto MonikerParams::textDocument(TextDocumentIdentifier textDocument)
     -> MonikerParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto MonikerParams::position(Position position) -> MonikerParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -2994,6 +2959,7 @@ Moniker::operator bool() const {
 auto Moniker::scheme() const -> std::string {
   auto& value = (*repr_)["scheme"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -3001,6 +2967,7 @@ auto Moniker::scheme() const -> std::string {
 auto Moniker::identifier() const -> std::string {
   auto& value = (*repr_)["identifier"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -3020,12 +2987,12 @@ auto Moniker::kind() const -> std::optional<MonikerKind> {
 }
 
 auto Moniker::scheme(std::string scheme) -> Moniker& {
-  repr_->emplace("scheme", std::move(scheme));
+  (*repr_)["scheme"] = std::move(scheme);
   return *this;
 }
 
 auto Moniker::identifier(std::string identifier) -> Moniker& {
-  repr_->emplace("identifier", std::move(identifier));
+  (*repr_)["identifier"] = std::move(identifier);
   return *this;
 }
 
@@ -3050,10 +3017,10 @@ MonikerRegistrationOptions::operator bool() const {
 }
 
 auto MonikerRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -3066,29 +3033,24 @@ auto MonikerRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto MonikerRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> MonikerRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> MonikerRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "MonikerRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -3103,7 +3065,7 @@ auto MonikerRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -3142,13 +3104,13 @@ auto TypeHierarchyPrepareParams::workDoneToken() const
 
 auto TypeHierarchyPrepareParams::textDocument(
     TextDocumentIdentifier textDocument) -> TypeHierarchyPrepareParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto TypeHierarchyPrepareParams::position(Position position)
     -> TypeHierarchyPrepareParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -3176,6 +3138,7 @@ TypeHierarchyItem::operator bool() const {
 auto TypeHierarchyItem::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -3191,7 +3154,7 @@ auto TypeHierarchyItem::tags() const -> std::optional<Vector<SymbolTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SymbolTag>(value);
 }
 
@@ -3200,6 +3163,7 @@ auto TypeHierarchyItem::detail() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["detail"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -3207,6 +3171,7 @@ auto TypeHierarchyItem::detail() const -> std::optional<std::string> {
 auto TypeHierarchyItem::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -3233,12 +3198,12 @@ auto TypeHierarchyItem::data() const -> std::optional<LSPAny> {
 }
 
 auto TypeHierarchyItem::name(std::string name) -> TypeHierarchyItem& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
 auto TypeHierarchyItem::kind(SymbolKind kind) -> TypeHierarchyItem& {
-  repr_->emplace("kind", static_cast<long>(kind));
+  (*repr_)["kind"] = static_cast<long>(kind);
   return *this;
 }
 
@@ -3258,23 +3223,23 @@ auto TypeHierarchyItem::detail(std::optional<std::string> detail)
     repr_->erase("detail");
     return *this;
   }
-  repr_->emplace("detail", std::move(detail.value()));
+  (*repr_)["detail"] = std::move(detail.value());
   return *this;
 }
 
 auto TypeHierarchyItem::uri(std::string uri) -> TypeHierarchyItem& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto TypeHierarchyItem::range(Range range) -> TypeHierarchyItem& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto TypeHierarchyItem::selectionRange(Range selectionRange)
     -> TypeHierarchyItem& {
-  repr_->emplace("selectionRange", selectionRange);
+  (*repr_)["selectionRange"] = selectionRange;
   return *this;
 }
 
@@ -3294,10 +3259,10 @@ TypeHierarchyRegistrationOptions::operator bool() const {
 }
 
 auto TypeHierarchyRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -3310,6 +3275,7 @@ auto TypeHierarchyRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -3320,22 +3286,17 @@ auto TypeHierarchyRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TypeHierarchyRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> TypeHierarchyRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> TypeHierarchyRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "TypeHierarchyRegistrationOptions::documentSelector: not implement "
@@ -3343,7 +3304,7 @@ auto TypeHierarchyRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -3358,7 +3319,7 @@ auto TypeHierarchyRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -3368,7 +3329,7 @@ auto TypeHierarchyRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -3412,7 +3373,7 @@ auto TypeHierarchySupertypesParams::partialResultToken() const
 
 auto TypeHierarchySupertypesParams::item(TypeHierarchyItem item)
     -> TypeHierarchySupertypesParams& {
-  repr_->emplace("item", item);
+  (*repr_)["item"] = item;
   return *this;
 }
 
@@ -3480,7 +3441,7 @@ auto TypeHierarchySubtypesParams::partialResultToken() const
 
 auto TypeHierarchySubtypesParams::item(TypeHierarchyItem item)
     -> TypeHierarchySubtypesParams& {
-  repr_->emplace("item", item);
+  (*repr_)["item"] = item;
   return *this;
 }
 
@@ -3548,18 +3509,18 @@ auto InlineValueParams::workDoneToken() const -> std::optional<ProgressToken> {
 
 auto InlineValueParams::textDocument(TextDocumentIdentifier textDocument)
     -> InlineValueParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto InlineValueParams::range(Range range) -> InlineValueParams& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto InlineValueParams::context(InlineValueContext context)
     -> InlineValueParams& {
-  repr_->emplace("context", context);
+  (*repr_)["context"] = context;
   return *this;
 }
 
@@ -3585,15 +3546,16 @@ auto InlineValueRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto InlineValueRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -3605,6 +3567,7 @@ auto InlineValueRegistrationOptions::id() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -3615,22 +3578,16 @@ auto InlineValueRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
 auto InlineValueRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> InlineValueRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> InlineValueRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "InlineValueRegistrationOptions::documentSelector: not implement "
@@ -3638,7 +3595,7 @@ auto InlineValueRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -3653,7 +3610,7 @@ auto InlineValueRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -3690,12 +3647,12 @@ auto InlayHintParams::workDoneToken() const -> std::optional<ProgressToken> {
 
 auto InlayHintParams::textDocument(TextDocumentIdentifier textDocument)
     -> InlayHintParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto InlayHintParams::range(Range range) -> InlayHintParams& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -3723,10 +3680,10 @@ auto InlayHint::position() const -> Position {
 }
 
 auto InlayHint::label() const
-    -> std::variant<std::monostate, std::string, Vector<InlayHintLabelPart>> {
+    -> std::variant<std::string, Vector<InlayHintLabelPart>> {
   auto& value = (*repr_)["label"];
 
-  std::variant<std::monostate, std::string, Vector<InlayHintLabelPart>> result;
+  std::variant<std::string, Vector<InlayHintLabelPart>> result;
 
   details::try_emplace(result, value);
 
@@ -3746,17 +3703,17 @@ auto InlayHint::textEdits() const -> std::optional<Vector<TextEdit>> {
 
   auto& value = (*repr_)["textEdits"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextEdit>(value);
 }
 
 auto InlayHint::tooltip() const
-    -> std::optional<std::variant<std::monostate, std::string, MarkupContent>> {
+    -> std::optional<std::variant<std::string, MarkupContent>> {
   if (!repr_->contains("tooltip")) return std::nullopt;
 
   auto& value = (*repr_)["tooltip"];
 
-  std::variant<std::monostate, std::string, MarkupContent> result;
+  std::variant<std::string, MarkupContent> result;
 
   details::try_emplace(result, value);
 
@@ -3768,6 +3725,7 @@ auto InlayHint::paddingLeft() const -> std::optional<bool> {
 
   auto& value = (*repr_)["paddingLeft"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -3777,6 +3735,7 @@ auto InlayHint::paddingRight() const -> std::optional<bool> {
 
   auto& value = (*repr_)["paddingRight"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -3791,25 +3750,16 @@ auto InlayHint::data() const -> std::optional<LSPAny> {
 }
 
 auto InlayHint::position(Position position) -> InlayHint& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
 auto InlayHint::label(
-    std::variant<std::monostate, std::string, Vector<InlayHintLabelPart>> label)
-    -> InlayHint& {
-  // or type
-
+    std::variant<std::string, Vector<InlayHintLabelPart>> label) -> InlayHint& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(std::string label) {
-      repr_->emplace("label", std::move(label));
-    }
+    void operator()(std::string label) { (*repr_)["label"] = std::move(label); }
 
     void operator()(Vector<InlayHintLabelPart> label) {
       lsp_runtime_error("InlayHint::label: not implement yet");
@@ -3826,7 +3776,7 @@ auto InlayHint::kind(std::optional<InlayHintKind> kind) -> InlayHint& {
     repr_->erase("kind");
     return *this;
   }
-  repr_->emplace("kind", static_cast<long>(kind.value()));
+  (*repr_)["kind"] = static_cast<long>(kind.value());
   return *this;
 }
 
@@ -3841,29 +3791,21 @@ auto InlayHint::textEdits(std::optional<Vector<TextEdit>> textEdits)
 }
 
 auto InlayHint::tooltip(
-    std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-        tooltip) -> InlayHint& {
+    std::optional<std::variant<std::string, MarkupContent>> tooltip)
+    -> InlayHint& {
   if (!tooltip.has_value()) {
     repr_->erase("tooltip");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string tooltip) {
-      repr_->emplace("tooltip", std::move(tooltip));
+      (*repr_)["tooltip"] = std::move(tooltip);
     }
 
-    void operator()(MarkupContent tooltip) {
-      repr_->emplace("tooltip", tooltip);
-    }
+    void operator()(MarkupContent tooltip) { (*repr_)["tooltip"] = tooltip; }
   } v{repr_};
 
   std::visit(v, tooltip.value());
@@ -3876,7 +3818,7 @@ auto InlayHint::paddingLeft(std::optional<bool> paddingLeft) -> InlayHint& {
     repr_->erase("paddingLeft");
     return *this;
   }
-  repr_->emplace("paddingLeft", std::move(paddingLeft.value()));
+  (*repr_)["paddingLeft"] = std::move(paddingLeft.value());
   return *this;
 }
 
@@ -3885,7 +3827,7 @@ auto InlayHint::paddingRight(std::optional<bool> paddingRight) -> InlayHint& {
     repr_->erase("paddingRight");
     return *this;
   }
-  repr_->emplace("paddingRight", std::move(paddingRight.value()));
+  (*repr_)["paddingRight"] = std::move(paddingRight.value());
   return *this;
 }
 
@@ -3910,6 +3852,7 @@ auto InlayHintRegistrationOptions::resolveProvider() const
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -3920,15 +3863,16 @@ auto InlayHintRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto InlayHintRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -3940,6 +3884,7 @@ auto InlayHintRegistrationOptions::id() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -3950,7 +3895,7 @@ auto InlayHintRegistrationOptions::resolveProvider(
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -3960,29 +3905,23 @@ auto InlayHintRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
 auto InlayHintRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> InlayHintRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> InlayHintRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "InlayHintRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -3997,7 +3936,7 @@ auto InlayHintRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -4019,6 +3958,7 @@ auto DocumentDiagnosticParams::identifier() const
 
   auto& value = (*repr_)["identifier"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -4029,6 +3969,7 @@ auto DocumentDiagnosticParams::previousResultId() const
 
   auto& value = (*repr_)["previousResultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -4061,7 +4002,7 @@ auto DocumentDiagnosticParams::partialResultToken() const
 
 auto DocumentDiagnosticParams::textDocument(TextDocumentIdentifier textDocument)
     -> DocumentDiagnosticParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -4071,7 +4012,7 @@ auto DocumentDiagnosticParams::identifier(std::optional<std::string> identifier)
     repr_->erase("identifier");
     return *this;
   }
-  repr_->emplace("identifier", std::move(identifier.value()));
+  (*repr_)["identifier"] = std::move(identifier.value());
   return *this;
 }
 
@@ -4081,7 +4022,7 @@ auto DocumentDiagnosticParams::previousResultId(
     repr_->erase("previousResultId");
     return *this;
   }
-  repr_->emplace("previousResultId", std::move(previousResultId.value()));
+  (*repr_)["previousResultId"] = std::move(previousResultId.value());
   return *this;
 }
 
@@ -4115,19 +4056,18 @@ DocumentDiagnosticReportPartialResult::operator bool() const {
 }
 
 auto DocumentDiagnosticReportPartialResult::relatedDocuments() const
-    -> Map<std::string,
-           std::variant<std::monostate, FullDocumentDiagnosticReport,
-                        UnchangedDocumentDiagnosticReport>> {
+    -> Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                     UnchangedDocumentDiagnosticReport>> {
   auto& value = (*repr_)["relatedDocuments"];
 
-  assert(value.is_object());
-  return Map<std::string,
-             std::variant<std::monostate, FullDocumentDiagnosticReport,
-                          UnchangedDocumentDiagnosticReport>>(value);
+  if (value.is_null()) value = json::object();
+  return Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                       UnchangedDocumentDiagnosticReport>>(
+      value);
 }
 
 auto DocumentDiagnosticReportPartialResult::relatedDocuments(
-    Map<std::string, std::variant<std::monostate, FullDocumentDiagnosticReport,
+    Map<std::string, std::variant<FullDocumentDiagnosticReport,
                                   UnchangedDocumentDiagnosticReport>>
         relatedDocuments) -> DocumentDiagnosticReportPartialResult& {
   lsp_runtime_error(
@@ -4145,13 +4085,14 @@ DiagnosticServerCancellationData::operator bool() const {
 auto DiagnosticServerCancellationData::retriggerRequest() const -> bool {
   auto& value = (*repr_)["retriggerRequest"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto DiagnosticServerCancellationData::retriggerRequest(bool retriggerRequest)
     -> DiagnosticServerCancellationData& {
-  repr_->emplace("retriggerRequest", std::move(retriggerRequest));
+  (*repr_)["retriggerRequest"] = std::move(retriggerRequest);
   return *this;
 }
 
@@ -4164,10 +4105,10 @@ DiagnosticRegistrationOptions::operator bool() const {
 }
 
 auto DiagnosticRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -4180,6 +4121,7 @@ auto DiagnosticRegistrationOptions::identifier() const
 
   auto& value = (*repr_)["identifier"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -4187,6 +4129,7 @@ auto DiagnosticRegistrationOptions::identifier() const
 auto DiagnosticRegistrationOptions::interFileDependencies() const -> bool {
   auto& value = (*repr_)["interFileDependencies"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -4194,6 +4137,7 @@ auto DiagnosticRegistrationOptions::interFileDependencies() const -> bool {
 auto DiagnosticRegistrationOptions::workspaceDiagnostics() const -> bool {
   auto& value = (*repr_)["workspaceDiagnostics"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -4204,6 +4148,7 @@ auto DiagnosticRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -4213,29 +4158,24 @@ auto DiagnosticRegistrationOptions::id() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto DiagnosticRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DiagnosticRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DiagnosticRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DiagnosticRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -4250,19 +4190,19 @@ auto DiagnosticRegistrationOptions::identifier(
     repr_->erase("identifier");
     return *this;
   }
-  repr_->emplace("identifier", std::move(identifier.value()));
+  (*repr_)["identifier"] = std::move(identifier.value());
   return *this;
 }
 
 auto DiagnosticRegistrationOptions::interFileDependencies(
     bool interFileDependencies) -> DiagnosticRegistrationOptions& {
-  repr_->emplace("interFileDependencies", std::move(interFileDependencies));
+  (*repr_)["interFileDependencies"] = std::move(interFileDependencies);
   return *this;
 }
 
 auto DiagnosticRegistrationOptions::workspaceDiagnostics(
     bool workspaceDiagnostics) -> DiagnosticRegistrationOptions& {
-  repr_->emplace("workspaceDiagnostics", std::move(workspaceDiagnostics));
+  (*repr_)["workspaceDiagnostics"] = std::move(workspaceDiagnostics);
   return *this;
 }
 
@@ -4272,7 +4212,7 @@ auto DiagnosticRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -4282,7 +4222,7 @@ auto DiagnosticRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -4298,6 +4238,7 @@ auto WorkspaceDiagnosticParams::identifier() const
 
   auto& value = (*repr_)["identifier"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -4306,7 +4247,7 @@ auto WorkspaceDiagnosticParams::previousResultIds() const
     -> Vector<PreviousResultId> {
   auto& value = (*repr_)["previousResultIds"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<PreviousResultId>(value);
 }
 
@@ -4342,7 +4283,7 @@ auto WorkspaceDiagnosticParams::identifier(
     repr_->erase("identifier");
     return *this;
   }
-  repr_->emplace("identifier", std::move(identifier.value()));
+  (*repr_)["identifier"] = std::move(identifier.value());
   return *this;
 }
 
@@ -4386,7 +4327,7 @@ auto WorkspaceDiagnosticReport::items() const
     -> Vector<WorkspaceDocumentDiagnosticReport> {
   auto& value = (*repr_)["items"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<WorkspaceDocumentDiagnosticReport>(value);
 }
 
@@ -4407,7 +4348,7 @@ auto WorkspaceDiagnosticReportPartialResult::items() const
     -> Vector<WorkspaceDocumentDiagnosticReport> {
   auto& value = (*repr_)["items"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<WorkspaceDocumentDiagnosticReport>(value);
 }
 
@@ -4437,13 +4378,13 @@ auto DidOpenNotebookDocumentParams::cellTextDocuments() const
     -> Vector<TextDocumentItem> {
   auto& value = (*repr_)["cellTextDocuments"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextDocumentItem>(value);
 }
 
 auto DidOpenNotebookDocumentParams::notebookDocument(
     NotebookDocument notebookDocument) -> DidOpenNotebookDocumentParams& {
-  repr_->emplace("notebookDocument", notebookDocument);
+  (*repr_)["notebookDocument"] = notebookDocument;
   return *this;
 }
 
@@ -4462,12 +4403,12 @@ NotebookDocumentSyncRegistrationOptions::operator bool() const {
 }
 
 auto NotebookDocumentSyncRegistrationOptions::notebookSelector() const
-    -> Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
+    -> Vector<std::variant<NotebookDocumentFilterWithNotebook,
                            NotebookDocumentFilterWithCells>> {
   auto& value = (*repr_)["notebookSelector"];
 
-  assert(value.is_array());
-  return Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
+  if (value.is_null()) value = json::array();
+  return Vector<std::variant<NotebookDocumentFilterWithNotebook,
                              NotebookDocumentFilterWithCells>>(value);
 }
 
@@ -4477,6 +4418,7 @@ auto NotebookDocumentSyncRegistrationOptions::save() const
 
   auto& value = (*repr_)["save"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -4487,12 +4429,13 @@ auto NotebookDocumentSyncRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto NotebookDocumentSyncRegistrationOptions::notebookSelector(
-    Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
+    Vector<std::variant<NotebookDocumentFilterWithNotebook,
                         NotebookDocumentFilterWithCells>>
         notebookSelector) -> NotebookDocumentSyncRegistrationOptions& {
   lsp_runtime_error(
@@ -4507,7 +4450,7 @@ auto NotebookDocumentSyncRegistrationOptions::save(std::optional<bool> save)
     repr_->erase("save");
     return *this;
   }
-  repr_->emplace("save", std::move(save.value()));
+  (*repr_)["save"] = std::move(save.value());
   return *this;
 }
 
@@ -4517,7 +4460,7 @@ auto NotebookDocumentSyncRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -4545,13 +4488,13 @@ auto DidChangeNotebookDocumentParams::change() const
 auto DidChangeNotebookDocumentParams::notebookDocument(
     VersionedNotebookDocumentIdentifier notebookDocument)
     -> DidChangeNotebookDocumentParams& {
-  repr_->emplace("notebookDocument", notebookDocument);
+  (*repr_)["notebookDocument"] = notebookDocument;
   return *this;
 }
 
 auto DidChangeNotebookDocumentParams::change(NotebookDocumentChangeEvent change)
     -> DidChangeNotebookDocumentParams& {
-  repr_->emplace("change", change);
+  (*repr_)["change"] = change;
   return *this;
 }
 
@@ -4571,7 +4514,7 @@ auto DidSaveNotebookDocumentParams::notebookDocument() const
 auto DidSaveNotebookDocumentParams::notebookDocument(
     NotebookDocumentIdentifier notebookDocument)
     -> DidSaveNotebookDocumentParams& {
-  repr_->emplace("notebookDocument", notebookDocument);
+  (*repr_)["notebookDocument"] = notebookDocument;
   return *this;
 }
 
@@ -4593,14 +4536,14 @@ auto DidCloseNotebookDocumentParams::cellTextDocuments() const
     -> Vector<TextDocumentIdentifier> {
   auto& value = (*repr_)["cellTextDocuments"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextDocumentIdentifier>(value);
 }
 
 auto DidCloseNotebookDocumentParams::notebookDocument(
     NotebookDocumentIdentifier notebookDocument)
     -> DidCloseNotebookDocumentParams& {
-  repr_->emplace("notebookDocument", notebookDocument);
+  (*repr_)["notebookDocument"] = notebookDocument;
   return *this;
 }
 
@@ -4653,19 +4596,19 @@ auto InlineCompletionParams::workDoneToken() const
 
 auto InlineCompletionParams::context(InlineCompletionContext context)
     -> InlineCompletionParams& {
-  repr_->emplace("context", context);
+  (*repr_)["context"] = context;
   return *this;
 }
 
 auto InlineCompletionParams::textDocument(TextDocumentIdentifier textDocument)
     -> InlineCompletionParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto InlineCompletionParams::position(Position position)
     -> InlineCompletionParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -4688,7 +4631,7 @@ InlineCompletionList::operator bool() const {
 auto InlineCompletionList::items() const -> Vector<InlineCompletionItem> {
   auto& value = (*repr_)["items"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<InlineCompletionItem>(value);
 }
 
@@ -4705,10 +4648,10 @@ InlineCompletionItem::operator bool() const {
 }
 
 auto InlineCompletionItem::insertText() const
-    -> std::variant<std::monostate, std::string, StringValue> {
+    -> std::variant<std::string, StringValue> {
   auto& value = (*repr_)["insertText"];
 
-  std::variant<std::monostate, std::string, StringValue> result;
+  std::variant<std::string, StringValue> result;
 
   details::try_emplace(result, value);
 
@@ -4720,6 +4663,7 @@ auto InlineCompletionItem::filterText() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["filterText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -4741,23 +4685,17 @@ auto InlineCompletionItem::command() const -> std::optional<Command> {
 }
 
 auto InlineCompletionItem::insertText(
-    std::variant<std::monostate, std::string, StringValue> insertText)
+    std::variant<std::string, StringValue> insertText)
     -> InlineCompletionItem& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string insertText) {
-      repr_->emplace("insertText", std::move(insertText));
+      (*repr_)["insertText"] = std::move(insertText);
     }
 
     void operator()(StringValue insertText) {
-      repr_->emplace("insertText", insertText);
+      (*repr_)["insertText"] = insertText;
     }
   } v{repr_};
 
@@ -4772,7 +4710,7 @@ auto InlineCompletionItem::filterText(std::optional<std::string> filterText)
     repr_->erase("filterText");
     return *this;
   }
-  repr_->emplace("filterText", std::move(filterText.value()));
+  (*repr_)["filterText"] = std::move(filterText.value());
   return *this;
 }
 
@@ -4782,7 +4720,7 @@ auto InlineCompletionItem::range(std::optional<Range> range)
     repr_->erase("range");
     return *this;
   }
-  repr_->emplace("range", range.value());
+  (*repr_)["range"] = range.value();
   return *this;
 }
 
@@ -4792,7 +4730,7 @@ auto InlineCompletionItem::command(std::optional<Command> command)
     repr_->erase("command");
     return *this;
   }
-  repr_->emplace("command", command.value());
+  (*repr_)["command"] = command.value();
   return *this;
 }
 
@@ -4808,15 +4746,16 @@ auto InlineCompletionRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto InlineCompletionRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -4829,6 +4768,7 @@ auto InlineCompletionRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -4840,22 +4780,16 @@ auto InlineCompletionRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
 auto InlineCompletionRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> InlineCompletionRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> InlineCompletionRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "InlineCompletionRegistrationOptions::documentSelector: not "
@@ -4863,7 +4797,7 @@ auto InlineCompletionRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -4878,7 +4812,7 @@ auto InlineCompletionRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -4891,13 +4825,14 @@ TextDocumentContentParams::operator bool() const {
 auto TextDocumentContentParams::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TextDocumentContentParams::uri(std::string uri)
     -> TextDocumentContentParams& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -4910,13 +4845,14 @@ TextDocumentContentResult::operator bool() const {
 auto TextDocumentContentResult::text() const -> std::string {
   auto& value = (*repr_)["text"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TextDocumentContentResult::text(std::string text)
     -> TextDocumentContentResult& {
-  repr_->emplace("text", std::move(text));
+  (*repr_)["text"] = std::move(text);
   return *this;
 }
 
@@ -4930,7 +4866,7 @@ auto TextDocumentContentRegistrationOptions::schemes() const
     -> Vector<std::string> {
   auto& value = (*repr_)["schemes"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -4940,6 +4876,7 @@ auto TextDocumentContentRegistrationOptions::id() const
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -4957,7 +4894,7 @@ auto TextDocumentContentRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -4970,13 +4907,14 @@ TextDocumentContentRefreshParams::operator bool() const {
 auto TextDocumentContentRefreshParams::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TextDocumentContentRefreshParams::uri(std::string uri)
     -> TextDocumentContentRefreshParams& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -4989,7 +4927,7 @@ RegistrationParams::operator bool() const {
 auto RegistrationParams::registrations() const -> Vector<Registration> {
   auto& value = (*repr_)["registrations"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Registration>(value);
 }
 
@@ -5008,7 +4946,7 @@ UnregistrationParams::operator bool() const {
 auto UnregistrationParams::unregisterations() const -> Vector<Unregistration> {
   auto& value = (*repr_)["unregisterations"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Unregistration>(value);
 }
 
@@ -5027,11 +4965,10 @@ InitializeParams::operator bool() const {
   return true;
 }
 
-auto InitializeParams::processId() const
-    -> std::variant<std::monostate, int, std::nullptr_t> {
+auto InitializeParams::processId() const -> std::variant<int, std::nullptr_t> {
   auto& value = (*repr_)["processId"];
 
-  std::variant<std::monostate, int, std::nullptr_t> result;
+  std::variant<int, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -5051,17 +4988,18 @@ auto InitializeParams::locale() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["locale"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
-auto InitializeParams::rootPath() const -> std::optional<
-    std::variant<std::monostate, std::string, std::nullptr_t>> {
+auto InitializeParams::rootPath() const
+    -> std::optional<std::variant<std::string, std::nullptr_t>> {
   if (!repr_->contains("rootPath")) return std::nullopt;
 
   auto& value = (*repr_)["rootPath"];
 
-  std::variant<std::monostate, std::string, std::nullptr_t> result;
+  std::variant<std::string, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -5069,10 +5007,10 @@ auto InitializeParams::rootPath() const -> std::optional<
 }
 
 auto InitializeParams::rootUri() const
-    -> std::variant<std::monostate, std::string, std::nullptr_t> {
+    -> std::variant<std::string, std::nullptr_t> {
   auto& value = (*repr_)["rootUri"];
 
-  std::variant<std::monostate, std::string, std::nullptr_t> result;
+  std::variant<std::string, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -5114,37 +5052,30 @@ auto InitializeParams::workDoneToken() const -> std::optional<ProgressToken> {
   return result;
 }
 
-auto InitializeParams::workspaceFolders() const -> std::optional<
-    std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t>> {
+auto InitializeParams::workspaceFolders() const
+    -> std::optional<std::variant<Vector<WorkspaceFolder>, std::nullptr_t>> {
   if (!repr_->contains("workspaceFolders")) return std::nullopt;
 
   auto& value = (*repr_)["workspaceFolders"];
 
-  std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t> result;
+  std::variant<Vector<WorkspaceFolder>, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto InitializeParams::processId(
-    std::variant<std::monostate, int, std::nullptr_t> processId)
+auto InitializeParams::processId(std::variant<int, std::nullptr_t> processId)
     -> InitializeParams& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(int processId) {
-      repr_->emplace("processId", std::move(processId));
+      (*repr_)["processId"] = std::move(processId);
     }
 
     void operator()(std::nullptr_t processId) {
-      repr_->emplace("processId", std::move(processId));
+      (*repr_)["processId"] = std::move(processId);
     }
   } v{repr_};
 
@@ -5159,7 +5090,7 @@ auto InitializeParams::clientInfo(std::optional<ClientInfo> clientInfo)
     repr_->erase("clientInfo");
     return *this;
   }
-  repr_->emplace("clientInfo", clientInfo.value());
+  (*repr_)["clientInfo"] = clientInfo.value();
   return *this;
 }
 
@@ -5169,33 +5100,27 @@ auto InitializeParams::locale(std::optional<std::string> locale)
     repr_->erase("locale");
     return *this;
   }
-  repr_->emplace("locale", std::move(locale.value()));
+  (*repr_)["locale"] = std::move(locale.value());
   return *this;
 }
 
 auto InitializeParams::rootPath(
-    std::optional<std::variant<std::monostate, std::string, std::nullptr_t>>
-        rootPath) -> InitializeParams& {
+    std::optional<std::variant<std::string, std::nullptr_t>> rootPath)
+    -> InitializeParams& {
   if (!rootPath.has_value()) {
     repr_->erase("rootPath");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string rootPath) {
-      repr_->emplace("rootPath", std::move(rootPath));
+      (*repr_)["rootPath"] = std::move(rootPath);
     }
 
     void operator()(std::nullptr_t rootPath) {
-      repr_->emplace("rootPath", std::move(rootPath));
+      (*repr_)["rootPath"] = std::move(rootPath);
     }
   } v{repr_};
 
@@ -5205,23 +5130,16 @@ auto InitializeParams::rootPath(
 }
 
 auto InitializeParams::rootUri(
-    std::variant<std::monostate, std::string, std::nullptr_t> rootUri)
-    -> InitializeParams& {
-  // or type
-
+    std::variant<std::string, std::nullptr_t> rootUri) -> InitializeParams& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string rootUri) {
-      repr_->emplace("rootUri", std::move(rootUri));
+      (*repr_)["rootUri"] = std::move(rootUri);
     }
 
     void operator()(std::nullptr_t rootUri) {
-      repr_->emplace("rootUri", std::move(rootUri));
+      (*repr_)["rootUri"] = std::move(rootUri);
     }
   } v{repr_};
 
@@ -5232,7 +5150,7 @@ auto InitializeParams::rootUri(
 
 auto InitializeParams::capabilities(ClientCapabilities capabilities)
     -> InitializeParams& {
-  repr_->emplace("capabilities", capabilities);
+  (*repr_)["capabilities"] = capabilities;
   return *this;
 }
 
@@ -5268,30 +5186,23 @@ auto InitializeParams::workDoneToken(std::optional<ProgressToken> workDoneToken)
 }
 
 auto InitializeParams::workspaceFolders(
-    std::optional<
-        std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t>>
+    std::optional<std::variant<Vector<WorkspaceFolder>, std::nullptr_t>>
         workspaceFolders) -> InitializeParams& {
   if (!workspaceFolders.has_value()) {
     repr_->erase("workspaceFolders");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(Vector<WorkspaceFolder> workspaceFolders) {
       lsp_runtime_error(
           "InitializeParams::workspaceFolders: not implement yet");
     }
 
     void operator()(std::nullptr_t workspaceFolders) {
-      repr_->emplace("workspaceFolders", std::move(workspaceFolders));
+      (*repr_)["workspaceFolders"] = std::move(workspaceFolders);
     }
   } v{repr_};
 
@@ -5322,7 +5233,7 @@ auto InitializeResult::serverInfo() const -> std::optional<ServerInfo> {
 
 auto InitializeResult::capabilities(ServerCapabilities capabilities)
     -> InitializeResult& {
-  repr_->emplace("capabilities", capabilities);
+  (*repr_)["capabilities"] = capabilities;
   return *this;
 }
 
@@ -5332,7 +5243,7 @@ auto InitializeResult::serverInfo(std::optional<ServerInfo> serverInfo)
     repr_->erase("serverInfo");
     return *this;
   }
-  repr_->emplace("serverInfo", serverInfo.value());
+  (*repr_)["serverInfo"] = serverInfo.value();
   return *this;
 }
 
@@ -5345,12 +5256,13 @@ InitializeError::operator bool() const {
 auto InitializeError::retry() const -> bool {
   auto& value = (*repr_)["retry"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto InitializeError::retry(bool retry) -> InitializeError& {
-  repr_->emplace("retry", std::move(retry));
+  (*repr_)["retry"] = std::move(retry);
   return *this;
 }
 
@@ -5385,13 +5297,12 @@ DidChangeConfigurationRegistrationOptions::operator bool() const {
 }
 
 auto DidChangeConfigurationRegistrationOptions::section() const
-    -> std::optional<
-        std::variant<std::monostate, std::string, Vector<std::string>>> {
+    -> std::optional<std::variant<std::string, Vector<std::string>>> {
   if (!repr_->contains("section")) return std::nullopt;
 
   auto& value = (*repr_)["section"];
 
-  std::variant<std::monostate, std::string, Vector<std::string>> result;
+  std::variant<std::string, Vector<std::string>> result;
 
   details::try_emplace(result, value);
 
@@ -5399,25 +5310,18 @@ auto DidChangeConfigurationRegistrationOptions::section() const
 }
 
 auto DidChangeConfigurationRegistrationOptions::section(
-    std::optional<
-        std::variant<std::monostate, std::string, Vector<std::string>>>
-        section) -> DidChangeConfigurationRegistrationOptions& {
+    std::optional<std::variant<std::string, Vector<std::string>>> section)
+    -> DidChangeConfigurationRegistrationOptions& {
   if (!section.has_value()) {
     repr_->erase("section");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string section) {
-      repr_->emplace("section", std::move(section));
+      (*repr_)["section"] = std::move(section);
     }
 
     void operator()(Vector<std::string> section) {
@@ -5448,17 +5352,18 @@ auto ShowMessageParams::type() const -> MessageType {
 auto ShowMessageParams::message() const -> std::string {
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto ShowMessageParams::type(MessageType type) -> ShowMessageParams& {
-  repr_->emplace("type", static_cast<long>(type));
+  (*repr_)["type"] = static_cast<long>(type);
   return *this;
 }
 
 auto ShowMessageParams::message(std::string message) -> ShowMessageParams& {
-  repr_->emplace("message", std::move(message));
+  (*repr_)["message"] = std::move(message);
   return *this;
 }
 
@@ -5478,6 +5383,7 @@ auto ShowMessageRequestParams::type() const -> MessageType {
 auto ShowMessageRequestParams::message() const -> std::string {
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -5488,19 +5394,19 @@ auto ShowMessageRequestParams::actions() const
 
   auto& value = (*repr_)["actions"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<MessageActionItem>(value);
 }
 
 auto ShowMessageRequestParams::type(MessageType type)
     -> ShowMessageRequestParams& {
-  repr_->emplace("type", static_cast<long>(type));
+  (*repr_)["type"] = static_cast<long>(type);
   return *this;
 }
 
 auto ShowMessageRequestParams::message(std::string message)
     -> ShowMessageRequestParams& {
-  repr_->emplace("message", std::move(message));
+  (*repr_)["message"] = std::move(message);
   return *this;
 }
 
@@ -5524,12 +5430,13 @@ MessageActionItem::operator bool() const {
 auto MessageActionItem::title() const -> std::string {
   auto& value = (*repr_)["title"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto MessageActionItem::title(std::string title) -> MessageActionItem& {
-  repr_->emplace("title", std::move(title));
+  (*repr_)["title"] = std::move(title);
   return *this;
 }
 
@@ -5549,17 +5456,18 @@ auto LogMessageParams::type() const -> MessageType {
 auto LogMessageParams::message() const -> std::string {
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto LogMessageParams::type(MessageType type) -> LogMessageParams& {
-  repr_->emplace("type", static_cast<long>(type));
+  (*repr_)["type"] = static_cast<long>(type);
   return *this;
 }
 
 auto LogMessageParams::message(std::string message) -> LogMessageParams& {
-  repr_->emplace("message", std::move(message));
+  (*repr_)["message"] = std::move(message);
   return *this;
 }
 
@@ -5577,7 +5485,7 @@ auto DidOpenTextDocumentParams::textDocument() const -> TextDocumentItem {
 
 auto DidOpenTextDocumentParams::textDocument(TextDocumentItem textDocument)
     -> DidOpenTextDocumentParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -5599,14 +5507,14 @@ auto DidChangeTextDocumentParams::contentChanges() const
     -> Vector<TextDocumentContentChangeEvent> {
   auto& value = (*repr_)["contentChanges"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextDocumentContentChangeEvent>(value);
 }
 
 auto DidChangeTextDocumentParams::textDocument(
     VersionedTextDocumentIdentifier textDocument)
     -> DidChangeTextDocumentParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -5633,10 +5541,10 @@ auto TextDocumentChangeRegistrationOptions::syncKind() const
 }
 
 auto TextDocumentChangeRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -5645,22 +5553,16 @@ auto TextDocumentChangeRegistrationOptions::documentSelector() const
 
 auto TextDocumentChangeRegistrationOptions::syncKind(
     TextDocumentSyncKind syncKind) -> TextDocumentChangeRegistrationOptions& {
-  repr_->emplace("syncKind", static_cast<long>(syncKind));
+  (*repr_)["syncKind"] = static_cast<long>(syncKind);
   return *this;
 }
 
 auto TextDocumentChangeRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> TextDocumentChangeRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> TextDocumentChangeRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "TextDocumentChangeRegistrationOptions::documentSelector: not "
@@ -5668,7 +5570,7 @@ auto TextDocumentChangeRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -5692,7 +5594,7 @@ auto DidCloseTextDocumentParams::textDocument() const
 
 auto DidCloseTextDocumentParams::textDocument(
     TextDocumentIdentifier textDocument) -> DidCloseTextDocumentParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -5713,13 +5615,14 @@ auto DidSaveTextDocumentParams::text() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["text"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto DidSaveTextDocumentParams::textDocument(
     TextDocumentIdentifier textDocument) -> DidSaveTextDocumentParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -5729,7 +5632,7 @@ auto DidSaveTextDocumentParams::text(std::optional<std::string> text)
     repr_->erase("text");
     return *this;
   }
-  repr_->emplace("text", std::move(text.value()));
+  (*repr_)["text"] = std::move(text.value());
   return *this;
 }
 
@@ -5740,10 +5643,10 @@ TextDocumentSaveRegistrationOptions::operator bool() const {
 }
 
 auto TextDocumentSaveRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -5756,22 +5659,17 @@ auto TextDocumentSaveRegistrationOptions::includeText() const
 
   auto& value = (*repr_)["includeText"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto TextDocumentSaveRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> TextDocumentSaveRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> TextDocumentSaveRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "TextDocumentSaveRegistrationOptions::documentSelector: not "
@@ -5779,7 +5677,7 @@ auto TextDocumentSaveRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -5794,7 +5692,7 @@ auto TextDocumentSaveRegistrationOptions::includeText(
     repr_->erase("includeText");
     return *this;
   }
-  repr_->emplace("includeText", std::move(includeText.value()));
+  (*repr_)["includeText"] = std::move(includeText.value());
   return *this;
 }
 
@@ -5820,13 +5718,13 @@ auto WillSaveTextDocumentParams::reason() const -> TextDocumentSaveReason {
 
 auto WillSaveTextDocumentParams::textDocument(
     TextDocumentIdentifier textDocument) -> WillSaveTextDocumentParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto WillSaveTextDocumentParams::reason(TextDocumentSaveReason reason)
     -> WillSaveTextDocumentParams& {
-  repr_->emplace("reason", static_cast<long>(reason));
+  (*repr_)["reason"] = static_cast<long>(reason);
   return *this;
 }
 
@@ -5846,17 +5744,18 @@ auto TextEdit::range() const -> Range {
 auto TextEdit::newText() const -> std::string {
   auto& value = (*repr_)["newText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TextEdit::range(Range range) -> TextEdit& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto TextEdit::newText(std::string newText) -> TextEdit& {
-  repr_->emplace("newText", std::move(newText));
+  (*repr_)["newText"] = std::move(newText);
   return *this;
 }
 
@@ -5869,7 +5768,7 @@ DidChangeWatchedFilesParams::operator bool() const {
 auto DidChangeWatchedFilesParams::changes() const -> Vector<FileEvent> {
   auto& value = (*repr_)["changes"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<FileEvent>(value);
 }
 
@@ -5889,7 +5788,7 @@ auto DidChangeWatchedFilesRegistrationOptions::watchers() const
     -> Vector<FileSystemWatcher> {
   auto& value = (*repr_)["watchers"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<FileSystemWatcher>(value);
 }
 
@@ -5911,6 +5810,7 @@ PublishDiagnosticsParams::operator bool() const {
 auto PublishDiagnosticsParams::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -5920,6 +5820,7 @@ auto PublishDiagnosticsParams::version() const -> std::optional<int> {
 
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<int>();
 }
@@ -5927,13 +5828,13 @@ auto PublishDiagnosticsParams::version() const -> std::optional<int> {
 auto PublishDiagnosticsParams::diagnostics() const -> Vector<Diagnostic> {
   auto& value = (*repr_)["diagnostics"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Diagnostic>(value);
 }
 
 auto PublishDiagnosticsParams::uri(std::string uri)
     -> PublishDiagnosticsParams& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -5943,7 +5844,7 @@ auto PublishDiagnosticsParams::version(std::optional<int> version)
     repr_->erase("version");
     return *this;
   }
-  repr_->emplace("version", std::move(version.value()));
+  (*repr_)["version"] = std::move(version.value());
   return *this;
 }
 
@@ -6011,18 +5912,18 @@ auto CompletionParams::context(std::optional<CompletionContext> context)
     repr_->erase("context");
     return *this;
   }
-  repr_->emplace("context", context.value());
+  (*repr_)["context"] = context.value();
   return *this;
 }
 
 auto CompletionParams::textDocument(TextDocumentIdentifier textDocument)
     -> CompletionParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto CompletionParams::position(Position position) -> CompletionParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -6055,6 +5956,7 @@ CompletionItem::operator bool() const {
 auto CompletionItem::label() const -> std::string {
   auto& value = (*repr_)["label"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -6081,7 +5983,7 @@ auto CompletionItem::tags() const -> std::optional<Vector<CompletionItemTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CompletionItemTag>(value);
 }
 
@@ -6090,17 +5992,18 @@ auto CompletionItem::detail() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["detail"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto CompletionItem::documentation() const
-    -> std::optional<std::variant<std::monostate, std::string, MarkupContent>> {
+    -> std::optional<std::variant<std::string, MarkupContent>> {
   if (!repr_->contains("documentation")) return std::nullopt;
 
   auto& value = (*repr_)["documentation"];
 
-  std::variant<std::monostate, std::string, MarkupContent> result;
+  std::variant<std::string, MarkupContent> result;
 
   details::try_emplace(result, value);
 
@@ -6112,6 +6015,7 @@ auto CompletionItem::deprecated() const -> std::optional<bool> {
 
   auto& value = (*repr_)["deprecated"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -6121,6 +6025,7 @@ auto CompletionItem::preselect() const -> std::optional<bool> {
 
   auto& value = (*repr_)["preselect"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -6130,6 +6035,7 @@ auto CompletionItem::sortText() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["sortText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -6139,6 +6045,7 @@ auto CompletionItem::filterText() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["filterText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -6148,6 +6055,7 @@ auto CompletionItem::insertText() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["insertText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -6169,13 +6077,13 @@ auto CompletionItem::insertTextMode() const -> std::optional<InsertTextMode> {
   return InsertTextMode(value);
 }
 
-auto CompletionItem::textEdit() const -> std::optional<
-    std::variant<std::monostate, TextEdit, InsertReplaceEdit>> {
+auto CompletionItem::textEdit() const
+    -> std::optional<std::variant<TextEdit, InsertReplaceEdit>> {
   if (!repr_->contains("textEdit")) return std::nullopt;
 
   auto& value = (*repr_)["textEdit"];
 
-  std::variant<std::monostate, TextEdit, InsertReplaceEdit> result;
+  std::variant<TextEdit, InsertReplaceEdit> result;
 
   details::try_emplace(result, value);
 
@@ -6187,6 +6095,7 @@ auto CompletionItem::textEditText() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["textEditText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -6197,7 +6106,7 @@ auto CompletionItem::additionalTextEdits() const
 
   auto& value = (*repr_)["additionalTextEdits"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextEdit>(value);
 }
 
@@ -6207,7 +6116,7 @@ auto CompletionItem::commitCharacters() const
 
   auto& value = (*repr_)["commitCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -6229,7 +6138,7 @@ auto CompletionItem::data() const -> std::optional<LSPAny> {
 }
 
 auto CompletionItem::label(std::string label) -> CompletionItem& {
-  repr_->emplace("label", std::move(label));
+  (*repr_)["label"] = std::move(label);
   return *this;
 }
 
@@ -6239,7 +6148,7 @@ auto CompletionItem::labelDetails(
     repr_->erase("labelDetails");
     return *this;
   }
-  repr_->emplace("labelDetails", labelDetails.value());
+  (*repr_)["labelDetails"] = labelDetails.value();
   return *this;
 }
 
@@ -6249,7 +6158,7 @@ auto CompletionItem::kind(std::optional<CompletionItemKind> kind)
     repr_->erase("kind");
     return *this;
   }
-  repr_->emplace("kind", static_cast<long>(kind.value()));
+  (*repr_)["kind"] = static_cast<long>(kind.value());
   return *this;
 }
 
@@ -6269,33 +6178,27 @@ auto CompletionItem::detail(std::optional<std::string> detail)
     repr_->erase("detail");
     return *this;
   }
-  repr_->emplace("detail", std::move(detail.value()));
+  (*repr_)["detail"] = std::move(detail.value());
   return *this;
 }
 
 auto CompletionItem::documentation(
-    std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-        documentation) -> CompletionItem& {
+    std::optional<std::variant<std::string, MarkupContent>> documentation)
+    -> CompletionItem& {
   if (!documentation.has_value()) {
     repr_->erase("documentation");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string documentation) {
-      repr_->emplace("documentation", std::move(documentation));
+      (*repr_)["documentation"] = std::move(documentation);
     }
 
     void operator()(MarkupContent documentation) {
-      repr_->emplace("documentation", documentation);
+      (*repr_)["documentation"] = documentation;
     }
   } v{repr_};
 
@@ -6310,7 +6213,7 @@ auto CompletionItem::deprecated(std::optional<bool> deprecated)
     repr_->erase("deprecated");
     return *this;
   }
-  repr_->emplace("deprecated", std::move(deprecated.value()));
+  (*repr_)["deprecated"] = std::move(deprecated.value());
   return *this;
 }
 
@@ -6320,7 +6223,7 @@ auto CompletionItem::preselect(std::optional<bool> preselect)
     repr_->erase("preselect");
     return *this;
   }
-  repr_->emplace("preselect", std::move(preselect.value()));
+  (*repr_)["preselect"] = std::move(preselect.value());
   return *this;
 }
 
@@ -6330,7 +6233,7 @@ auto CompletionItem::sortText(std::optional<std::string> sortText)
     repr_->erase("sortText");
     return *this;
   }
-  repr_->emplace("sortText", std::move(sortText.value()));
+  (*repr_)["sortText"] = std::move(sortText.value());
   return *this;
 }
 
@@ -6340,7 +6243,7 @@ auto CompletionItem::filterText(std::optional<std::string> filterText)
     repr_->erase("filterText");
     return *this;
   }
-  repr_->emplace("filterText", std::move(filterText.value()));
+  (*repr_)["filterText"] = std::move(filterText.value());
   return *this;
 }
 
@@ -6350,7 +6253,7 @@ auto CompletionItem::insertText(std::optional<std::string> insertText)
     repr_->erase("insertText");
     return *this;
   }
-  repr_->emplace("insertText", std::move(insertText.value()));
+  (*repr_)["insertText"] = std::move(insertText.value());
   return *this;
 }
 
@@ -6360,8 +6263,7 @@ auto CompletionItem::insertTextFormat(
     repr_->erase("insertTextFormat");
     return *this;
   }
-  repr_->emplace("insertTextFormat",
-                 static_cast<long>(insertTextFormat.value()));
+  (*repr_)["insertTextFormat"] = static_cast<long>(insertTextFormat.value());
   return *this;
 }
 
@@ -6371,31 +6273,25 @@ auto CompletionItem::insertTextMode(
     repr_->erase("insertTextMode");
     return *this;
   }
-  repr_->emplace("insertTextMode", static_cast<long>(insertTextMode.value()));
+  (*repr_)["insertTextMode"] = static_cast<long>(insertTextMode.value());
   return *this;
 }
 
 auto CompletionItem::textEdit(
-    std::optional<std::variant<std::monostate, TextEdit, InsertReplaceEdit>>
-        textEdit) -> CompletionItem& {
+    std::optional<std::variant<TextEdit, InsertReplaceEdit>> textEdit)
+    -> CompletionItem& {
   if (!textEdit.has_value()) {
     repr_->erase("textEdit");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(TextEdit textEdit) { repr_->emplace("textEdit", textEdit); }
+    void operator()(TextEdit textEdit) { (*repr_)["textEdit"] = textEdit; }
 
     void operator()(InsertReplaceEdit textEdit) {
-      repr_->emplace("textEdit", textEdit);
+      (*repr_)["textEdit"] = textEdit;
     }
   } v{repr_};
 
@@ -6410,7 +6306,7 @@ auto CompletionItem::textEditText(std::optional<std::string> textEditText)
     repr_->erase("textEditText");
     return *this;
   }
-  repr_->emplace("textEditText", std::move(textEditText.value()));
+  (*repr_)["textEditText"] = std::move(textEditText.value());
   return *this;
 }
 
@@ -6440,7 +6336,7 @@ auto CompletionItem::command(std::optional<Command> command)
     repr_->erase("command");
     return *this;
   }
-  repr_->emplace("command", command.value());
+  (*repr_)["command"] = command.value();
   return *this;
 }
 
@@ -6463,6 +6359,7 @@ CompletionList::operator bool() const {
 auto CompletionList::isIncomplete() const -> bool {
   auto& value = (*repr_)["isIncomplete"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -6488,12 +6385,12 @@ auto CompletionList::applyKind() const
 auto CompletionList::items() const -> Vector<CompletionItem> {
   auto& value = (*repr_)["items"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CompletionItem>(value);
 }
 
 auto CompletionList::isIncomplete(bool isIncomplete) -> CompletionList& {
-  repr_->emplace("isIncomplete", std::move(isIncomplete));
+  (*repr_)["isIncomplete"] = std::move(isIncomplete);
   return *this;
 }
 
@@ -6503,7 +6400,7 @@ auto CompletionList::itemDefaults(
     repr_->erase("itemDefaults");
     return *this;
   }
-  repr_->emplace("itemDefaults", itemDefaults.value());
+  (*repr_)["itemDefaults"] = itemDefaults.value();
   return *this;
 }
 
@@ -6513,7 +6410,7 @@ auto CompletionList::applyKind(
     repr_->erase("applyKind");
     return *this;
   }
-  repr_->emplace("applyKind", applyKind.value());
+  (*repr_)["applyKind"] = applyKind.value();
   return *this;
 }
 
@@ -6529,10 +6426,10 @@ CompletionRegistrationOptions::operator bool() const {
 }
 
 auto CompletionRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -6545,7 +6442,7 @@ auto CompletionRegistrationOptions::triggerCharacters() const
 
   auto& value = (*repr_)["triggerCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -6555,7 +6452,7 @@ auto CompletionRegistrationOptions::allCommitCharacters() const
 
   auto& value = (*repr_)["allCommitCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -6565,6 +6462,7 @@ auto CompletionRegistrationOptions::resolveProvider() const
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -6584,29 +6482,24 @@ auto CompletionRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto CompletionRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> CompletionRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> CompletionRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "CompletionRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -6645,7 +6538,7 @@ auto CompletionRegistrationOptions::resolveProvider(
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -6656,7 +6549,7 @@ auto CompletionRegistrationOptions::completionItem(
     repr_->erase("completionItem");
     return *this;
   }
-  repr_->emplace("completionItem", completionItem.value());
+  (*repr_)["completionItem"] = completionItem.value();
   return *this;
 }
 
@@ -6666,7 +6559,7 @@ auto CompletionRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -6703,12 +6596,12 @@ auto HoverParams::workDoneToken() const -> std::optional<ProgressToken> {
 
 auto HoverParams::textDocument(TextDocumentIdentifier textDocument)
     -> HoverParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto HoverParams::position(Position position) -> HoverParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -6729,13 +6622,10 @@ Hover::operator bool() const {
 }
 
 auto Hover::contents() const
-    -> std::variant<std::monostate, MarkupContent, MarkedString,
-                    Vector<MarkedString>> {
+    -> std::variant<MarkupContent, MarkedString, Vector<MarkedString>> {
   auto& value = (*repr_)["contents"];
 
-  std::variant<std::monostate, MarkupContent, MarkedString,
-               Vector<MarkedString>>
-      result;
+  std::variant<MarkupContent, MarkedString, Vector<MarkedString>> result;
 
   details::try_emplace(result, value);
 
@@ -6750,21 +6640,13 @@ auto Hover::range() const -> std::optional<Range> {
   return Range(value);
 }
 
-auto Hover::contents(std::variant<std::monostate, MarkupContent, MarkedString,
-                                  Vector<MarkedString>>
-                         contents) -> Hover& {
-  // or type
-
+auto Hover::contents(
+    std::variant<MarkupContent, MarkedString, Vector<MarkedString>> contents)
+    -> Hover& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(MarkupContent contents) {
-      repr_->emplace("contents", contents);
-    }
+    void operator()(MarkupContent contents) { (*repr_)["contents"] = contents; }
 
     void operator()(MarkedString contents) {
       lsp_runtime_error("Hover::contents: not implement yet");
@@ -6785,7 +6667,7 @@ auto Hover::range(std::optional<Range> range) -> Hover& {
     repr_->erase("range");
     return *this;
   }
-  repr_->emplace("range", range.value());
+  (*repr_)["range"] = range.value();
   return *this;
 }
 
@@ -6796,10 +6678,10 @@ HoverRegistrationOptions::operator bool() const {
 }
 
 auto HoverRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -6811,29 +6693,24 @@ auto HoverRegistrationOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto HoverRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> HoverRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> HoverRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "HoverRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -6848,7 +6725,7 @@ auto HoverRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -6899,18 +6776,18 @@ auto SignatureHelpParams::context(std::optional<SignatureHelpContext> context)
     repr_->erase("context");
     return *this;
   }
-  repr_->emplace("context", context.value());
+  (*repr_)["context"] = context.value();
   return *this;
 }
 
 auto SignatureHelpParams::textDocument(TextDocumentIdentifier textDocument)
     -> SignatureHelpParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto SignatureHelpParams::position(Position position) -> SignatureHelpParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -6933,7 +6810,7 @@ SignatureHelp::operator bool() const {
 auto SignatureHelp::signatures() const -> Vector<SignatureInformation> {
   auto& value = (*repr_)["signatures"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SignatureInformation>(value);
 }
 
@@ -6942,17 +6819,18 @@ auto SignatureHelp::activeSignature() const -> std::optional<long> {
 
   auto& value = (*repr_)["activeSignature"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
 
 auto SignatureHelp::activeParameter() const
-    -> std::optional<std::variant<std::monostate, long, std::nullptr_t>> {
+    -> std::optional<std::variant<long, std::nullptr_t>> {
   if (!repr_->contains("activeParameter")) return std::nullopt;
 
   auto& value = (*repr_)["activeParameter"];
 
-  std::variant<std::monostate, long, std::nullptr_t> result;
+  std::variant<long, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -6971,33 +6849,27 @@ auto SignatureHelp::activeSignature(std::optional<long> activeSignature)
     repr_->erase("activeSignature");
     return *this;
   }
-  repr_->emplace("activeSignature", std::move(activeSignature.value()));
+  (*repr_)["activeSignature"] = std::move(activeSignature.value());
   return *this;
 }
 
 auto SignatureHelp::activeParameter(
-    std::optional<std::variant<std::monostate, long, std::nullptr_t>>
-        activeParameter) -> SignatureHelp& {
+    std::optional<std::variant<long, std::nullptr_t>> activeParameter)
+    -> SignatureHelp& {
   if (!activeParameter.has_value()) {
     repr_->erase("activeParameter");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(long activeParameter) {
-      repr_->emplace("activeParameter", std::move(activeParameter));
+      (*repr_)["activeParameter"] = std::move(activeParameter);
     }
 
     void operator()(std::nullptr_t activeParameter) {
-      repr_->emplace("activeParameter", std::move(activeParameter));
+      (*repr_)["activeParameter"] = std::move(activeParameter);
     }
   } v{repr_};
 
@@ -7013,10 +6885,10 @@ SignatureHelpRegistrationOptions::operator bool() const {
 }
 
 auto SignatureHelpRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -7029,7 +6901,7 @@ auto SignatureHelpRegistrationOptions::triggerCharacters() const
 
   auto& value = (*repr_)["triggerCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -7039,7 +6911,7 @@ auto SignatureHelpRegistrationOptions::retriggerCharacters() const
 
   auto& value = (*repr_)["retriggerCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -7049,22 +6921,17 @@ auto SignatureHelpRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto SignatureHelpRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> SignatureHelpRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> SignatureHelpRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "SignatureHelpRegistrationOptions::documentSelector: not implement "
@@ -7072,7 +6939,7 @@ auto SignatureHelpRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -7112,7 +6979,7 @@ auto SignatureHelpRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -7162,12 +7029,12 @@ auto DefinitionParams::partialResultToken() const
 
 auto DefinitionParams::textDocument(TextDocumentIdentifier textDocument)
     -> DefinitionParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto DefinitionParams::position(Position position) -> DefinitionParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -7198,10 +7065,10 @@ DefinitionRegistrationOptions::operator bool() const {
 }
 
 auto DefinitionRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -7214,29 +7081,24 @@ auto DefinitionRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto DefinitionRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DefinitionRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DefinitionRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DefinitionRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -7251,7 +7113,7 @@ auto DefinitionRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -7307,18 +7169,18 @@ auto ReferenceParams::partialResultToken() const
 }
 
 auto ReferenceParams::context(ReferenceContext context) -> ReferenceParams& {
-  repr_->emplace("context", context);
+  (*repr_)["context"] = context;
   return *this;
 }
 
 auto ReferenceParams::textDocument(TextDocumentIdentifier textDocument)
     -> ReferenceParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto ReferenceParams::position(Position position) -> ReferenceParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -7349,10 +7211,10 @@ ReferenceRegistrationOptions::operator bool() const {
 }
 
 auto ReferenceRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -7365,29 +7227,24 @@ auto ReferenceRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto ReferenceRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> ReferenceRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> ReferenceRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "ReferenceRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -7402,7 +7259,7 @@ auto ReferenceRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -7453,13 +7310,13 @@ auto DocumentHighlightParams::partialResultToken() const
 
 auto DocumentHighlightParams::textDocument(TextDocumentIdentifier textDocument)
     -> DocumentHighlightParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto DocumentHighlightParams::position(Position position)
     -> DocumentHighlightParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -7507,7 +7364,7 @@ auto DocumentHighlight::kind() const -> std::optional<DocumentHighlightKind> {
 }
 
 auto DocumentHighlight::range(Range range) -> DocumentHighlight& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -7517,7 +7374,7 @@ auto DocumentHighlight::kind(std::optional<DocumentHighlightKind> kind)
     repr_->erase("kind");
     return *this;
   }
-  repr_->emplace("kind", static_cast<long>(kind.value()));
+  (*repr_)["kind"] = static_cast<long>(kind.value());
   return *this;
 }
 
@@ -7528,10 +7385,10 @@ DocumentHighlightRegistrationOptions::operator bool() const {
 }
 
 auto DocumentHighlightRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -7544,22 +7401,17 @@ auto DocumentHighlightRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto DocumentHighlightRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DocumentHighlightRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DocumentHighlightRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DocumentHighlightRegistrationOptions::documentSelector: not "
@@ -7567,7 +7419,7 @@ auto DocumentHighlightRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -7583,7 +7435,7 @@ auto DocumentHighlightRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -7627,7 +7479,7 @@ auto DocumentSymbolParams::partialResultToken() const
 
 auto DocumentSymbolParams::textDocument(TextDocumentIdentifier textDocument)
     -> DocumentSymbolParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -7665,6 +7517,7 @@ auto SymbolInformation::deprecated() const -> std::optional<bool> {
 
   auto& value = (*repr_)["deprecated"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -7678,6 +7531,7 @@ auto SymbolInformation::location() const -> Location {
 auto SymbolInformation::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -7693,7 +7547,7 @@ auto SymbolInformation::tags() const -> std::optional<Vector<SymbolTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SymbolTag>(value);
 }
 
@@ -7702,6 +7556,7 @@ auto SymbolInformation::containerName() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["containerName"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -7712,22 +7567,22 @@ auto SymbolInformation::deprecated(std::optional<bool> deprecated)
     repr_->erase("deprecated");
     return *this;
   }
-  repr_->emplace("deprecated", std::move(deprecated.value()));
+  (*repr_)["deprecated"] = std::move(deprecated.value());
   return *this;
 }
 
 auto SymbolInformation::location(Location location) -> SymbolInformation& {
-  repr_->emplace("location", location);
+  (*repr_)["location"] = location;
   return *this;
 }
 
 auto SymbolInformation::name(std::string name) -> SymbolInformation& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
 auto SymbolInformation::kind(SymbolKind kind) -> SymbolInformation& {
-  repr_->emplace("kind", static_cast<long>(kind));
+  (*repr_)["kind"] = static_cast<long>(kind);
   return *this;
 }
 
@@ -7747,7 +7602,7 @@ auto SymbolInformation::containerName(std::optional<std::string> containerName)
     repr_->erase("containerName");
     return *this;
   }
-  repr_->emplace("containerName", std::move(containerName.value()));
+  (*repr_)["containerName"] = std::move(containerName.value());
   return *this;
 }
 
@@ -7763,6 +7618,7 @@ DocumentSymbol::operator bool() const {
 auto DocumentSymbol::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -7772,6 +7628,7 @@ auto DocumentSymbol::detail() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["detail"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -7787,7 +7644,7 @@ auto DocumentSymbol::tags() const -> std::optional<Vector<SymbolTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SymbolTag>(value);
 }
 
@@ -7796,6 +7653,7 @@ auto DocumentSymbol::deprecated() const -> std::optional<bool> {
 
   auto& value = (*repr_)["deprecated"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -7817,12 +7675,12 @@ auto DocumentSymbol::children() const -> std::optional<Vector<DocumentSymbol>> {
 
   auto& value = (*repr_)["children"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<DocumentSymbol>(value);
 }
 
 auto DocumentSymbol::name(std::string name) -> DocumentSymbol& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
@@ -7832,12 +7690,12 @@ auto DocumentSymbol::detail(std::optional<std::string> detail)
     repr_->erase("detail");
     return *this;
   }
-  repr_->emplace("detail", std::move(detail.value()));
+  (*repr_)["detail"] = std::move(detail.value());
   return *this;
 }
 
 auto DocumentSymbol::kind(SymbolKind kind) -> DocumentSymbol& {
-  repr_->emplace("kind", static_cast<long>(kind));
+  (*repr_)["kind"] = static_cast<long>(kind);
   return *this;
 }
 
@@ -7857,17 +7715,17 @@ auto DocumentSymbol::deprecated(std::optional<bool> deprecated)
     repr_->erase("deprecated");
     return *this;
   }
-  repr_->emplace("deprecated", std::move(deprecated.value()));
+  (*repr_)["deprecated"] = std::move(deprecated.value());
   return *this;
 }
 
 auto DocumentSymbol::range(Range range) -> DocumentSymbol& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto DocumentSymbol::selectionRange(Range selectionRange) -> DocumentSymbol& {
-  repr_->emplace("selectionRange", selectionRange);
+  (*repr_)["selectionRange"] = selectionRange;
   return *this;
 }
 
@@ -7888,10 +7746,10 @@ DocumentSymbolRegistrationOptions::operator bool() const {
 }
 
 auto DocumentSymbolRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -7904,6 +7762,7 @@ auto DocumentSymbolRegistrationOptions::label() const
 
   auto& value = (*repr_)["label"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -7914,22 +7773,17 @@ auto DocumentSymbolRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto DocumentSymbolRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DocumentSymbolRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DocumentSymbolRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DocumentSymbolRegistrationOptions::documentSelector: not implement "
@@ -7937,7 +7791,7 @@ auto DocumentSymbolRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -7952,7 +7806,7 @@ auto DocumentSymbolRegistrationOptions::label(std::optional<std::string> label)
     repr_->erase("label");
     return *this;
   }
-  repr_->emplace("label", std::move(label.value()));
+  (*repr_)["label"] = std::move(label.value());
   return *this;
 }
 
@@ -7963,7 +7817,7 @@ auto DocumentSymbolRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -8020,17 +7874,17 @@ auto CodeActionParams::partialResultToken() const
 
 auto CodeActionParams::textDocument(TextDocumentIdentifier textDocument)
     -> CodeActionParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto CodeActionParams::range(Range range) -> CodeActionParams& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto CodeActionParams::context(CodeActionContext context) -> CodeActionParams& {
-  repr_->emplace("context", context);
+  (*repr_)["context"] = context;
   return *this;
 }
 
@@ -8064,6 +7918,7 @@ Command::operator bool() const {
 auto Command::title() const -> std::string {
   auto& value = (*repr_)["title"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -8073,6 +7928,7 @@ auto Command::tooltip() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["tooltip"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -8080,6 +7936,7 @@ auto Command::tooltip() const -> std::optional<std::string> {
 auto Command::command() const -> std::string {
   auto& value = (*repr_)["command"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -8089,12 +7946,12 @@ auto Command::arguments() const -> std::optional<Vector<LSPAny>> {
 
   auto& value = (*repr_)["arguments"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<LSPAny>(value);
 }
 
 auto Command::title(std::string title) -> Command& {
-  repr_->emplace("title", std::move(title));
+  (*repr_)["title"] = std::move(title);
   return *this;
 }
 
@@ -8103,12 +7960,12 @@ auto Command::tooltip(std::optional<std::string> tooltip) -> Command& {
     repr_->erase("tooltip");
     return *this;
   }
-  repr_->emplace("tooltip", std::move(tooltip.value()));
+  (*repr_)["tooltip"] = std::move(tooltip.value());
   return *this;
 }
 
 auto Command::command(std::string command) -> Command& {
-  repr_->emplace("command", std::move(command));
+  (*repr_)["command"] = std::move(command);
   return *this;
 }
 
@@ -8130,6 +7987,7 @@ CodeAction::operator bool() const {
 auto CodeAction::title() const -> std::string {
   auto& value = (*repr_)["title"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -8147,7 +8005,7 @@ auto CodeAction::diagnostics() const -> std::optional<Vector<Diagnostic>> {
 
   auto& value = (*repr_)["diagnostics"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Diagnostic>(value);
 }
 
@@ -8156,6 +8014,7 @@ auto CodeAction::isPreferred() const -> std::optional<bool> {
 
   auto& value = (*repr_)["isPreferred"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -8198,12 +8057,12 @@ auto CodeAction::tags() const -> std::optional<Vector<CodeActionTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CodeActionTag>(value);
 }
 
 auto CodeAction::title(std::string title) -> CodeAction& {
-  repr_->emplace("title", std::move(title));
+  (*repr_)["title"] = std::move(title);
   return *this;
 }
 
@@ -8231,7 +8090,7 @@ auto CodeAction::isPreferred(std::optional<bool> isPreferred) -> CodeAction& {
     repr_->erase("isPreferred");
     return *this;
   }
-  repr_->emplace("isPreferred", std::move(isPreferred.value()));
+  (*repr_)["isPreferred"] = std::move(isPreferred.value());
   return *this;
 }
 
@@ -8241,7 +8100,7 @@ auto CodeAction::disabled(std::optional<CodeActionDisabled> disabled)
     repr_->erase("disabled");
     return *this;
   }
-  repr_->emplace("disabled", disabled.value());
+  (*repr_)["disabled"] = disabled.value();
   return *this;
 }
 
@@ -8250,7 +8109,7 @@ auto CodeAction::edit(std::optional<WorkspaceEdit> edit) -> CodeAction& {
     repr_->erase("edit");
     return *this;
   }
-  repr_->emplace("edit", edit.value());
+  (*repr_)["edit"] = edit.value();
   return *this;
 }
 
@@ -8259,7 +8118,7 @@ auto CodeAction::command(std::optional<Command> command) -> CodeAction& {
     repr_->erase("command");
     return *this;
   }
-  repr_->emplace("command", command.value());
+  (*repr_)["command"] = command.value();
   return *this;
 }
 
@@ -8289,10 +8148,10 @@ CodeActionRegistrationOptions::operator bool() const {
 }
 
 auto CodeActionRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -8305,7 +8164,7 @@ auto CodeActionRegistrationOptions::codeActionKinds() const
 
   auto& value = (*repr_)["codeActionKinds"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CodeActionKind>(value);
 }
 
@@ -8315,7 +8174,7 @@ auto CodeActionRegistrationOptions::documentation() const
 
   auto& value = (*repr_)["documentation"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CodeActionKindDocumentation>(value);
 }
 
@@ -8325,6 +8184,7 @@ auto CodeActionRegistrationOptions::resolveProvider() const
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -8335,29 +8195,24 @@ auto CodeActionRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto CodeActionRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> CodeActionRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> CodeActionRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "CodeActionRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -8396,7 +8251,7 @@ auto CodeActionRegistrationOptions::resolveProvider(
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -8406,7 +8261,7 @@ auto CodeActionRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -8419,6 +8274,7 @@ WorkspaceSymbolParams::operator bool() const {
 auto WorkspaceSymbolParams::query() const -> std::string {
   auto& value = (*repr_)["query"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -8450,7 +8306,7 @@ auto WorkspaceSymbolParams::partialResultToken() const
 }
 
 auto WorkspaceSymbolParams::query(std::string query) -> WorkspaceSymbolParams& {
-  repr_->emplace("query", std::move(query));
+  (*repr_)["query"] = std::move(query);
   return *this;
 }
 
@@ -8484,10 +8340,10 @@ WorkspaceSymbol::operator bool() const {
 }
 
 auto WorkspaceSymbol::location() const
-    -> std::variant<std::monostate, Location, LocationUriOnly> {
+    -> std::variant<Location, LocationUriOnly> {
   auto& value = (*repr_)["location"];
 
-  std::variant<std::monostate, Location, LocationUriOnly> result;
+  std::variant<Location, LocationUriOnly> result;
 
   details::try_emplace(result, value);
 
@@ -8506,6 +8362,7 @@ auto WorkspaceSymbol::data() const -> std::optional<LSPAny> {
 auto WorkspaceSymbol::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -8521,7 +8378,7 @@ auto WorkspaceSymbol::tags() const -> std::optional<Vector<SymbolTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SymbolTag>(value);
 }
 
@@ -8530,26 +8387,20 @@ auto WorkspaceSymbol::containerName() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["containerName"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
-auto WorkspaceSymbol::location(
-    std::variant<std::monostate, Location, LocationUriOnly> location)
+auto WorkspaceSymbol::location(std::variant<Location, LocationUriOnly> location)
     -> WorkspaceSymbol& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(Location location) { repr_->emplace("location", location); }
+    void operator()(Location location) { (*repr_)["location"] = location; }
 
     void operator()(LocationUriOnly location) {
-      repr_->emplace("location", location);
+      (*repr_)["location"] = location;
     }
   } v{repr_};
 
@@ -8568,12 +8419,12 @@ auto WorkspaceSymbol::data(std::optional<LSPAny> data) -> WorkspaceSymbol& {
 }
 
 auto WorkspaceSymbol::name(std::string name) -> WorkspaceSymbol& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
 auto WorkspaceSymbol::kind(SymbolKind kind) -> WorkspaceSymbol& {
-  repr_->emplace("kind", static_cast<long>(kind));
+  (*repr_)["kind"] = static_cast<long>(kind);
   return *this;
 }
 
@@ -8593,7 +8444,7 @@ auto WorkspaceSymbol::containerName(std::optional<std::string> containerName)
     repr_->erase("containerName");
     return *this;
   }
-  repr_->emplace("containerName", std::move(containerName.value()));
+  (*repr_)["containerName"] = std::move(containerName.value());
   return *this;
 }
 
@@ -8608,6 +8459,7 @@ auto WorkspaceSymbolRegistrationOptions::resolveProvider() const
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -8618,6 +8470,7 @@ auto WorkspaceSymbolRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -8629,7 +8482,7 @@ auto WorkspaceSymbolRegistrationOptions::resolveProvider(
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -8640,7 +8493,7 @@ auto WorkspaceSymbolRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -8683,7 +8536,7 @@ auto CodeLensParams::partialResultToken() const
 
 auto CodeLensParams::textDocument(TextDocumentIdentifier textDocument)
     -> CodeLensParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -8737,7 +8590,7 @@ auto CodeLens::data() const -> std::optional<LSPAny> {
 }
 
 auto CodeLens::range(Range range) -> CodeLens& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -8746,7 +8599,7 @@ auto CodeLens::command(std::optional<Command> command) -> CodeLens& {
     repr_->erase("command");
     return *this;
   }
-  repr_->emplace("command", command.value());
+  (*repr_)["command"] = command.value();
   return *this;
 }
 
@@ -8766,10 +8619,10 @@ CodeLensRegistrationOptions::operator bool() const {
 }
 
 auto CodeLensRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -8782,6 +8635,7 @@ auto CodeLensRegistrationOptions::resolveProvider() const
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -8792,29 +8646,24 @@ auto CodeLensRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto CodeLensRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> CodeLensRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> CodeLensRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "CodeLensRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -8829,7 +8678,7 @@ auto CodeLensRegistrationOptions::resolveProvider(
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -8839,7 +8688,7 @@ auto CodeLensRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -8882,7 +8731,7 @@ auto DocumentLinkParams::partialResultToken() const
 
 auto DocumentLinkParams::textDocument(TextDocumentIdentifier textDocument)
     -> DocumentLinkParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -8924,6 +8773,7 @@ auto DocumentLink::target() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["target"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -8933,6 +8783,7 @@ auto DocumentLink::tooltip() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["tooltip"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -8947,7 +8798,7 @@ auto DocumentLink::data() const -> std::optional<LSPAny> {
 }
 
 auto DocumentLink::range(Range range) -> DocumentLink& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -8956,7 +8807,7 @@ auto DocumentLink::target(std::optional<std::string> target) -> DocumentLink& {
     repr_->erase("target");
     return *this;
   }
-  repr_->emplace("target", std::move(target.value()));
+  (*repr_)["target"] = std::move(target.value());
   return *this;
 }
 
@@ -8966,7 +8817,7 @@ auto DocumentLink::tooltip(std::optional<std::string> tooltip)
     repr_->erase("tooltip");
     return *this;
   }
-  repr_->emplace("tooltip", std::move(tooltip.value()));
+  (*repr_)["tooltip"] = std::move(tooltip.value());
   return *this;
 }
 
@@ -8986,10 +8837,10 @@ DocumentLinkRegistrationOptions::operator bool() const {
 }
 
 auto DocumentLinkRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -9002,6 +8853,7 @@ auto DocumentLinkRegistrationOptions::resolveProvider() const
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -9012,22 +8864,17 @@ auto DocumentLinkRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto DocumentLinkRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DocumentLinkRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DocumentLinkRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DocumentLinkRegistrationOptions::documentSelector: not implement "
@@ -9035,7 +8882,7 @@ auto DocumentLinkRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -9050,7 +8897,7 @@ auto DocumentLinkRegistrationOptions::resolveProvider(
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -9060,7 +8907,7 @@ auto DocumentLinkRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -9098,13 +8945,13 @@ auto DocumentFormattingParams::workDoneToken() const
 
 auto DocumentFormattingParams::textDocument(TextDocumentIdentifier textDocument)
     -> DocumentFormattingParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto DocumentFormattingParams::options(FormattingOptions options)
     -> DocumentFormattingParams& {
-  repr_->emplace("options", options);
+  (*repr_)["options"] = options;
   return *this;
 }
 
@@ -9126,10 +8973,10 @@ DocumentFormattingRegistrationOptions::operator bool() const {
 }
 
 auto DocumentFormattingRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -9142,22 +8989,17 @@ auto DocumentFormattingRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto DocumentFormattingRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DocumentFormattingRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DocumentFormattingRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DocumentFormattingRegistrationOptions::documentSelector: not "
@@ -9165,7 +9007,7 @@ auto DocumentFormattingRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -9181,7 +9023,7 @@ auto DocumentFormattingRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -9227,19 +9069,19 @@ auto DocumentRangeFormattingParams::workDoneToken() const
 
 auto DocumentRangeFormattingParams::textDocument(
     TextDocumentIdentifier textDocument) -> DocumentRangeFormattingParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto DocumentRangeFormattingParams::range(Range range)
     -> DocumentRangeFormattingParams& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto DocumentRangeFormattingParams::options(FormattingOptions options)
     -> DocumentRangeFormattingParams& {
-  repr_->emplace("options", options);
+  (*repr_)["options"] = options;
   return *this;
 }
 
@@ -9262,10 +9104,10 @@ DocumentRangeFormattingRegistrationOptions::operator bool() const {
 }
 
 auto DocumentRangeFormattingRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -9278,6 +9120,7 @@ auto DocumentRangeFormattingRegistrationOptions::rangesSupport() const
 
   auto& value = (*repr_)["rangesSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -9288,22 +9131,17 @@ auto DocumentRangeFormattingRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto DocumentRangeFormattingRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DocumentRangeFormattingRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DocumentRangeFormattingRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DocumentRangeFormattingRegistrationOptions::documentSelector: not "
@@ -9311,7 +9149,7 @@ auto DocumentRangeFormattingRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -9327,7 +9165,7 @@ auto DocumentRangeFormattingRegistrationOptions::rangesSupport(
     repr_->erase("rangesSupport");
     return *this;
   }
-  repr_->emplace("rangesSupport", std::move(rangesSupport.value()));
+  (*repr_)["rangesSupport"] = std::move(rangesSupport.value());
   return *this;
 }
 
@@ -9338,7 +9176,7 @@ auto DocumentRangeFormattingRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -9360,7 +9198,7 @@ auto DocumentRangesFormattingParams::textDocument() const
 auto DocumentRangesFormattingParams::ranges() const -> Vector<Range> {
   auto& value = (*repr_)["ranges"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Range>(value);
 }
 
@@ -9385,7 +9223,7 @@ auto DocumentRangesFormattingParams::workDoneToken() const
 
 auto DocumentRangesFormattingParams::textDocument(
     TextDocumentIdentifier textDocument) -> DocumentRangesFormattingParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
@@ -9398,7 +9236,7 @@ auto DocumentRangesFormattingParams::ranges(Vector<Range> ranges)
 
 auto DocumentRangesFormattingParams::options(FormattingOptions options)
     -> DocumentRangesFormattingParams& {
-  repr_->emplace("options", options);
+  (*repr_)["options"] = options;
   return *this;
 }
 
@@ -9439,6 +9277,7 @@ auto DocumentOnTypeFormattingParams::position() const -> Position {
 auto DocumentOnTypeFormattingParams::ch() const -> std::string {
   auto& value = (*repr_)["ch"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -9451,25 +9290,25 @@ auto DocumentOnTypeFormattingParams::options() const -> FormattingOptions {
 
 auto DocumentOnTypeFormattingParams::textDocument(
     TextDocumentIdentifier textDocument) -> DocumentOnTypeFormattingParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto DocumentOnTypeFormattingParams::position(Position position)
     -> DocumentOnTypeFormattingParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
 auto DocumentOnTypeFormattingParams::ch(std::string ch)
     -> DocumentOnTypeFormattingParams& {
-  repr_->emplace("ch", std::move(ch));
+  (*repr_)["ch"] = std::move(ch);
   return *this;
 }
 
 auto DocumentOnTypeFormattingParams::options(FormattingOptions options)
     -> DocumentOnTypeFormattingParams& {
-  repr_->emplace("options", options);
+  (*repr_)["options"] = options;
   return *this;
 }
 
@@ -9481,10 +9320,10 @@ DocumentOnTypeFormattingRegistrationOptions::operator bool() const {
 }
 
 auto DocumentOnTypeFormattingRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -9495,6 +9334,7 @@ auto DocumentOnTypeFormattingRegistrationOptions::firstTriggerCharacter() const
     -> std::string {
   auto& value = (*repr_)["firstTriggerCharacter"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -9505,22 +9345,16 @@ auto DocumentOnTypeFormattingRegistrationOptions::moreTriggerCharacter() const
 
   auto& value = (*repr_)["moreTriggerCharacter"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
 auto DocumentOnTypeFormattingRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> DocumentOnTypeFormattingRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> DocumentOnTypeFormattingRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "DocumentOnTypeFormattingRegistrationOptions::documentSelector: not "
@@ -9528,7 +9362,7 @@ auto DocumentOnTypeFormattingRegistrationOptions::documentSelector(
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -9540,7 +9374,7 @@ auto DocumentOnTypeFormattingRegistrationOptions::documentSelector(
 auto DocumentOnTypeFormattingRegistrationOptions::firstTriggerCharacter(
     std::string firstTriggerCharacter)
     -> DocumentOnTypeFormattingRegistrationOptions& {
-  repr_->emplace("firstTriggerCharacter", std::move(firstTriggerCharacter));
+  (*repr_)["firstTriggerCharacter"] = std::move(firstTriggerCharacter);
   return *this;
 }
 
@@ -9580,6 +9414,7 @@ auto RenameParams::position() const -> Position {
 auto RenameParams::newName() const -> std::string {
   auto& value = (*repr_)["newName"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -9598,17 +9433,17 @@ auto RenameParams::workDoneToken() const -> std::optional<ProgressToken> {
 
 auto RenameParams::textDocument(TextDocumentIdentifier textDocument)
     -> RenameParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto RenameParams::position(Position position) -> RenameParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
 auto RenameParams::newName(std::string newName) -> RenameParams& {
-  repr_->emplace("newName", std::move(newName));
+  (*repr_)["newName"] = std::move(newName);
   return *this;
 }
 
@@ -9629,10 +9464,10 @@ RenameRegistrationOptions::operator bool() const {
 }
 
 auto RenameRegistrationOptions::documentSelector() const
-    -> std::variant<std::monostate, DocumentSelector, std::nullptr_t> {
+    -> std::variant<DocumentSelector, std::nullptr_t> {
   auto& value = (*repr_)["documentSelector"];
 
-  std::variant<std::monostate, DocumentSelector, std::nullptr_t> result;
+  std::variant<DocumentSelector, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -9644,6 +9479,7 @@ auto RenameRegistrationOptions::prepareProvider() const -> std::optional<bool> {
 
   auto& value = (*repr_)["prepareProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -9654,29 +9490,24 @@ auto RenameRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto RenameRegistrationOptions::documentSelector(
-    std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-        documentSelector) -> RenameRegistrationOptions& {
-  // or type
-
+    std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+    -> RenameRegistrationOptions& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DocumentSelector documentSelector) {
       lsp_runtime_error(
           "RenameRegistrationOptions::documentSelector: not implement yet");
     }
 
     void operator()(std::nullptr_t documentSelector) {
-      repr_->emplace("documentSelector", std::move(documentSelector));
+      (*repr_)["documentSelector"] = std::move(documentSelector);
     }
   } v{repr_};
 
@@ -9691,7 +9522,7 @@ auto RenameRegistrationOptions::prepareProvider(
     repr_->erase("prepareProvider");
     return *this;
   }
-  repr_->emplace("prepareProvider", std::move(prepareProvider.value()));
+  (*repr_)["prepareProvider"] = std::move(prepareProvider.value());
   return *this;
 }
 
@@ -9701,7 +9532,7 @@ auto RenameRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -9739,12 +9570,12 @@ auto PrepareRenameParams::workDoneToken() const
 
 auto PrepareRenameParams::textDocument(TextDocumentIdentifier textDocument)
     -> PrepareRenameParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto PrepareRenameParams::position(Position position) -> PrepareRenameParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -9767,6 +9598,7 @@ ExecuteCommandParams::operator bool() const {
 auto ExecuteCommandParams::command() const -> std::string {
   auto& value = (*repr_)["command"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -9776,7 +9608,7 @@ auto ExecuteCommandParams::arguments() const -> std::optional<Vector<LSPAny>> {
 
   auto& value = (*repr_)["arguments"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<LSPAny>(value);
 }
 
@@ -9795,7 +9627,7 @@ auto ExecuteCommandParams::workDoneToken() const
 
 auto ExecuteCommandParams::command(std::string command)
     -> ExecuteCommandParams& {
-  repr_->emplace("command", std::move(command));
+  (*repr_)["command"] = std::move(command);
   return *this;
 }
 
@@ -9829,7 +9661,7 @@ auto ExecuteCommandRegistrationOptions::commands() const
     -> Vector<std::string> {
   auto& value = (*repr_)["commands"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -9839,6 +9671,7 @@ auto ExecuteCommandRegistrationOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -9857,7 +9690,7 @@ auto ExecuteCommandRegistrationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -9872,6 +9705,7 @@ auto ApplyWorkspaceEditParams::label() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["label"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -9897,13 +9731,13 @@ auto ApplyWorkspaceEditParams::label(std::optional<std::string> label)
     repr_->erase("label");
     return *this;
   }
-  repr_->emplace("label", std::move(label.value()));
+  (*repr_)["label"] = std::move(label.value());
   return *this;
 }
 
 auto ApplyWorkspaceEditParams::edit(WorkspaceEdit edit)
     -> ApplyWorkspaceEditParams& {
-  repr_->emplace("edit", edit);
+  (*repr_)["edit"] = edit;
   return *this;
 }
 
@@ -9914,7 +9748,7 @@ auto ApplyWorkspaceEditParams::metadata(
     repr_->erase("metadata");
     return *this;
   }
-  repr_->emplace("metadata", metadata.value());
+  (*repr_)["metadata"] = metadata.value();
   return *this;
 }
 
@@ -9927,6 +9761,7 @@ ApplyWorkspaceEditResult::operator bool() const {
 auto ApplyWorkspaceEditResult::applied() const -> bool {
   auto& value = (*repr_)["applied"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -9937,6 +9772,7 @@ auto ApplyWorkspaceEditResult::failureReason() const
 
   auto& value = (*repr_)["failureReason"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -9946,13 +9782,14 @@ auto ApplyWorkspaceEditResult::failedChange() const -> std::optional<long> {
 
   auto& value = (*repr_)["failedChange"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
 
 auto ApplyWorkspaceEditResult::applied(bool applied)
     -> ApplyWorkspaceEditResult& {
-  repr_->emplace("applied", std::move(applied));
+  (*repr_)["applied"] = std::move(applied);
   return *this;
 }
 
@@ -9962,7 +9799,7 @@ auto ApplyWorkspaceEditResult::failureReason(
     repr_->erase("failureReason");
     return *this;
   }
-  repr_->emplace("failureReason", std::move(failureReason.value()));
+  (*repr_)["failureReason"] = std::move(failureReason.value());
   return *this;
 }
 
@@ -9972,7 +9809,7 @@ auto ApplyWorkspaceEditResult::failedChange(std::optional<long> failedChange)
     repr_->erase("failedChange");
     return *this;
   }
-  repr_->emplace("failedChange", std::move(failedChange.value()));
+  (*repr_)["failedChange"] = std::move(failedChange.value());
   return *this;
 }
 
@@ -9987,6 +9824,7 @@ WorkDoneProgressBegin::operator bool() const {
 auto WorkDoneProgressBegin::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "begin";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -9994,6 +9832,7 @@ auto WorkDoneProgressBegin::kind() const -> std::string {
 auto WorkDoneProgressBegin::title() const -> std::string {
   auto& value = (*repr_)["title"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10003,6 +9842,7 @@ auto WorkDoneProgressBegin::cancellable() const -> std::optional<bool> {
 
   auto& value = (*repr_)["cancellable"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10012,6 +9852,7 @@ auto WorkDoneProgressBegin::message() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10021,6 +9862,7 @@ auto WorkDoneProgressBegin::percentage() const -> std::optional<long> {
 
   auto& value = (*repr_)["percentage"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -10031,7 +9873,7 @@ auto WorkDoneProgressBegin::kind(std::string kind) -> WorkDoneProgressBegin& {
 }
 
 auto WorkDoneProgressBegin::title(std::string title) -> WorkDoneProgressBegin& {
-  repr_->emplace("title", std::move(title));
+  (*repr_)["title"] = std::move(title);
   return *this;
 }
 
@@ -10041,7 +9883,7 @@ auto WorkDoneProgressBegin::cancellable(std::optional<bool> cancellable)
     repr_->erase("cancellable");
     return *this;
   }
-  repr_->emplace("cancellable", std::move(cancellable.value()));
+  (*repr_)["cancellable"] = std::move(cancellable.value());
   return *this;
 }
 
@@ -10051,7 +9893,7 @@ auto WorkDoneProgressBegin::message(std::optional<std::string> message)
     repr_->erase("message");
     return *this;
   }
-  repr_->emplace("message", std::move(message.value()));
+  (*repr_)["message"] = std::move(message.value());
   return *this;
 }
 
@@ -10061,7 +9903,7 @@ auto WorkDoneProgressBegin::percentage(std::optional<long> percentage)
     repr_->erase("percentage");
     return *this;
   }
-  repr_->emplace("percentage", std::move(percentage.value()));
+  (*repr_)["percentage"] = std::move(percentage.value());
   return *this;
 }
 
@@ -10075,6 +9917,7 @@ WorkDoneProgressReport::operator bool() const {
 auto WorkDoneProgressReport::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "report";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10084,6 +9927,7 @@ auto WorkDoneProgressReport::cancellable() const -> std::optional<bool> {
 
   auto& value = (*repr_)["cancellable"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10093,6 +9937,7 @@ auto WorkDoneProgressReport::message() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10102,6 +9947,7 @@ auto WorkDoneProgressReport::percentage() const -> std::optional<long> {
 
   auto& value = (*repr_)["percentage"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -10117,7 +9963,7 @@ auto WorkDoneProgressReport::cancellable(std::optional<bool> cancellable)
     repr_->erase("cancellable");
     return *this;
   }
-  repr_->emplace("cancellable", std::move(cancellable.value()));
+  (*repr_)["cancellable"] = std::move(cancellable.value());
   return *this;
 }
 
@@ -10127,7 +9973,7 @@ auto WorkDoneProgressReport::message(std::optional<std::string> message)
     repr_->erase("message");
     return *this;
   }
-  repr_->emplace("message", std::move(message.value()));
+  (*repr_)["message"] = std::move(message.value());
   return *this;
 }
 
@@ -10137,7 +9983,7 @@ auto WorkDoneProgressReport::percentage(std::optional<long> percentage)
     repr_->erase("percentage");
     return *this;
   }
-  repr_->emplace("percentage", std::move(percentage.value()));
+  (*repr_)["percentage"] = std::move(percentage.value());
   return *this;
 }
 
@@ -10151,6 +9997,7 @@ WorkDoneProgressEnd::operator bool() const {
 auto WorkDoneProgressEnd::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "end";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10160,6 +10007,7 @@ auto WorkDoneProgressEnd::message() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10175,7 +10023,7 @@ auto WorkDoneProgressEnd::message(std::optional<std::string> message)
     repr_->erase("message");
     return *this;
   }
-  repr_->emplace("message", std::move(message.value()));
+  (*repr_)["message"] = std::move(message.value());
   return *this;
 }
 
@@ -10205,6 +10053,7 @@ LogTraceParams::operator bool() const {
 auto LogTraceParams::message() const -> std::string {
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10214,12 +10063,13 @@ auto LogTraceParams::verbose() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["verbose"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto LogTraceParams::message(std::string message) -> LogTraceParams& {
-  repr_->emplace("message", std::move(message));
+  (*repr_)["message"] = std::move(message);
   return *this;
 }
 
@@ -10229,7 +10079,7 @@ auto LogTraceParams::verbose(std::optional<std::string> verbose)
     repr_->erase("verbose");
     return *this;
   }
-  repr_->emplace("verbose", std::move(verbose.value()));
+  (*repr_)["verbose"] = std::move(verbose.value());
   return *this;
 }
 
@@ -10239,31 +10089,23 @@ CancelParams::operator bool() const {
   return true;
 }
 
-auto CancelParams::id() const
-    -> std::variant<std::monostate, int, std::string> {
+auto CancelParams::id() const -> std::variant<int, std::string> {
   auto& value = (*repr_)["id"];
 
-  std::variant<std::monostate, int, std::string> result;
+  std::variant<int, std::string> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto CancelParams::id(std::variant<std::monostate, int, std::string> id)
-    -> CancelParams& {
-  // or type
-
+auto CancelParams::id(std::variant<int, std::string> id) -> CancelParams& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(int id) { repr_->emplace("id", std::move(id)); }
+    void operator()(int id) { (*repr_)["id"] = std::move(id); }
 
-    void operator()(std::string id) { repr_->emplace("id", std::move(id)); }
+    void operator()(std::string id) { (*repr_)["id"] = std::move(id); }
   } v{repr_};
 
   std::visit(v, id);
@@ -10327,13 +10169,13 @@ auto TextDocumentPositionParams::position() const -> Position {
 
 auto TextDocumentPositionParams::textDocument(
     TextDocumentIdentifier textDocument) -> TextDocumentPositionParams& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto TextDocumentPositionParams::position(Position position)
     -> TextDocumentPositionParams& {
-  repr_->emplace("position", position);
+  (*repr_)["position"] = position;
   return *this;
 }
 
@@ -10413,6 +10255,7 @@ auto LocationLink::originSelectionRange() const -> std::optional<Range> {
 auto LocationLink::targetUri() const -> std::string {
   auto& value = (*repr_)["targetUri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10435,23 +10278,23 @@ auto LocationLink::originSelectionRange(
     repr_->erase("originSelectionRange");
     return *this;
   }
-  repr_->emplace("originSelectionRange", originSelectionRange.value());
+  (*repr_)["originSelectionRange"] = originSelectionRange.value();
   return *this;
 }
 
 auto LocationLink::targetUri(std::string targetUri) -> LocationLink& {
-  repr_->emplace("targetUri", std::move(targetUri));
+  (*repr_)["targetUri"] = std::move(targetUri);
   return *this;
 }
 
 auto LocationLink::targetRange(Range targetRange) -> LocationLink& {
-  repr_->emplace("targetRange", targetRange);
+  (*repr_)["targetRange"] = targetRange;
   return *this;
 }
 
 auto LocationLink::targetSelectionRange(Range targetSelectionRange)
     -> LocationLink& {
-  repr_->emplace("targetSelectionRange", targetSelectionRange);
+  (*repr_)["targetSelectionRange"] = targetSelectionRange;
   return *this;
 }
 
@@ -10475,12 +10318,12 @@ auto Range::end() const -> Position {
 }
 
 auto Range::start(Position start) -> Range& {
-  repr_->emplace("start", start);
+  (*repr_)["start"] = start;
   return *this;
 }
 
 auto Range::end(Position end) -> Range& {
-  repr_->emplace("end", end);
+  (*repr_)["end"] = end;
   return *this;
 }
 
@@ -10494,6 +10337,7 @@ auto ImplementationOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10504,7 +10348,7 @@ auto ImplementationOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -10518,6 +10362,7 @@ auto StaticRegistrationOptions::id() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10528,7 +10373,7 @@ auto StaticRegistrationOptions::id(std::optional<std::string> id)
     repr_->erase("id");
     return *this;
   }
-  repr_->emplace("id", std::move(id.value()));
+  (*repr_)["id"] = std::move(id.value());
   return *this;
 }
 
@@ -10542,6 +10387,7 @@ auto TypeDefinitionOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10552,7 +10398,7 @@ auto TypeDefinitionOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -10566,14 +10412,14 @@ WorkspaceFoldersChangeEvent::operator bool() const {
 auto WorkspaceFoldersChangeEvent::added() const -> Vector<WorkspaceFolder> {
   auto& value = (*repr_)["added"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<WorkspaceFolder>(value);
 }
 
 auto WorkspaceFoldersChangeEvent::removed() const -> Vector<WorkspaceFolder> {
   auto& value = (*repr_)["removed"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<WorkspaceFolder>(value);
 }
 
@@ -10599,6 +10445,7 @@ auto ConfigurationItem::scopeUri() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["scopeUri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10608,6 +10455,7 @@ auto ConfigurationItem::section() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["section"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -10618,7 +10466,7 @@ auto ConfigurationItem::scopeUri(std::optional<std::string> scopeUri)
     repr_->erase("scopeUri");
     return *this;
   }
-  repr_->emplace("scopeUri", std::move(scopeUri.value()));
+  (*repr_)["scopeUri"] = std::move(scopeUri.value());
   return *this;
 }
 
@@ -10628,7 +10476,7 @@ auto ConfigurationItem::section(std::optional<std::string> section)
     repr_->erase("section");
     return *this;
   }
-  repr_->emplace("section", std::move(section.value()));
+  (*repr_)["section"] = std::move(section.value());
   return *this;
 }
 
@@ -10641,12 +10489,13 @@ TextDocumentIdentifier::operator bool() const {
 auto TextDocumentIdentifier::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TextDocumentIdentifier::uri(std::string uri) -> TextDocumentIdentifier& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -10662,6 +10511,7 @@ Color::operator bool() const {
 auto Color::red() const -> double {
   auto& value = (*repr_)["red"];
 
+  if (value.is_null()) value = 0.0;
   assert(value.is_number());
   return value.get<double>();
 }
@@ -10669,6 +10519,7 @@ auto Color::red() const -> double {
 auto Color::green() const -> double {
   auto& value = (*repr_)["green"];
 
+  if (value.is_null()) value = 0.0;
   assert(value.is_number());
   return value.get<double>();
 }
@@ -10676,6 +10527,7 @@ auto Color::green() const -> double {
 auto Color::blue() const -> double {
   auto& value = (*repr_)["blue"];
 
+  if (value.is_null()) value = 0.0;
   assert(value.is_number());
   return value.get<double>();
 }
@@ -10683,27 +10535,28 @@ auto Color::blue() const -> double {
 auto Color::alpha() const -> double {
   auto& value = (*repr_)["alpha"];
 
+  if (value.is_null()) value = 0.0;
   assert(value.is_number());
   return value.get<double>();
 }
 
 auto Color::red(double red) -> Color& {
-  repr_->emplace("red", std::move(red));
+  (*repr_)["red"] = std::move(red);
   return *this;
 }
 
 auto Color::green(double green) -> Color& {
-  repr_->emplace("green", std::move(green));
+  (*repr_)["green"] = std::move(green);
   return *this;
 }
 
 auto Color::blue(double blue) -> Color& {
-  repr_->emplace("blue", std::move(blue));
+  (*repr_)["blue"] = std::move(blue);
   return *this;
 }
 
 auto Color::alpha(double alpha) -> Color& {
-  repr_->emplace("alpha", std::move(alpha));
+  (*repr_)["alpha"] = std::move(alpha);
   return *this;
 }
 
@@ -10717,6 +10570,7 @@ auto DocumentColorOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10727,7 +10581,7 @@ auto DocumentColorOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -10741,6 +10595,7 @@ auto FoldingRangeOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10751,7 +10606,7 @@ auto FoldingRangeOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -10765,6 +10620,7 @@ auto DeclarationOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10775,7 +10631,7 @@ auto DeclarationOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -10789,6 +10645,7 @@ Position::operator bool() const {
 auto Position::line() const -> long {
   auto& value = (*repr_)["line"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -10796,17 +10653,18 @@ auto Position::line() const -> long {
 auto Position::character() const -> long {
   auto& value = (*repr_)["character"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
 
 auto Position::line(long line) -> Position& {
-  repr_->emplace("line", std::move(line));
+  (*repr_)["line"] = std::move(line);
   return *this;
 }
 
 auto Position::character(long character) -> Position& {
-  repr_->emplace("character", std::move(character));
+  (*repr_)["character"] = std::move(character);
   return *this;
 }
 
@@ -10820,6 +10678,7 @@ auto SelectionRangeOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10830,7 +10689,7 @@ auto SelectionRangeOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -10844,6 +10703,7 @@ auto CallHierarchyOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -10854,7 +10714,7 @@ auto CallHierarchyOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -10871,25 +10731,25 @@ auto SemanticTokensOptions::legend() const -> SemanticTokensLegend {
 }
 
 auto SemanticTokensOptions::range() const
-    -> std::optional<std::variant<std::monostate, bool, json>> {
+    -> std::optional<std::variant<bool, json>> {
   if (!repr_->contains("range")) return std::nullopt;
 
   auto& value = (*repr_)["range"];
 
-  std::variant<std::monostate, bool, json> result;
+  std::variant<bool, json> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto SemanticTokensOptions::full() const -> std::optional<
-    std::variant<std::monostate, bool, SemanticTokensFullDelta>> {
+auto SemanticTokensOptions::full() const
+    -> std::optional<std::variant<bool, SemanticTokensFullDelta>> {
   if (!repr_->contains("full")) return std::nullopt;
 
   auto& value = (*repr_)["full"];
 
-  std::variant<std::monostate, bool, SemanticTokensFullDelta> result;
+  std::variant<bool, SemanticTokensFullDelta> result;
 
   details::try_emplace(result, value);
 
@@ -10901,34 +10761,28 @@ auto SemanticTokensOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto SemanticTokensOptions::legend(SemanticTokensLegend legend)
     -> SemanticTokensOptions& {
-  repr_->emplace("legend", legend);
+  (*repr_)["legend"] = legend;
   return *this;
 }
 
-auto SemanticTokensOptions::range(
-    std::optional<std::variant<std::monostate, bool, json>> range)
+auto SemanticTokensOptions::range(std::optional<std::variant<bool, json>> range)
     -> SemanticTokensOptions& {
   if (!range.has_value()) {
     repr_->erase("range");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(bool range) { repr_->emplace("range", std::move(range)); }
+    void operator()(bool range) { (*repr_)["range"] = std::move(range); }
 
     void operator()(json range) {
       lsp_runtime_error("SemanticTokensOptions::range: not implement yet");
@@ -10941,27 +10795,19 @@ auto SemanticTokensOptions::range(
 }
 
 auto SemanticTokensOptions::full(
-    std::optional<std::variant<std::monostate, bool, SemanticTokensFullDelta>>
-        full) -> SemanticTokensOptions& {
+    std::optional<std::variant<bool, SemanticTokensFullDelta>> full)
+    -> SemanticTokensOptions& {
   if (!full.has_value()) {
     repr_->erase("full");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(bool full) { repr_->emplace("full", std::move(full)); }
+    void operator()(bool full) { (*repr_)["full"] = std::move(full); }
 
-    void operator()(SemanticTokensFullDelta full) {
-      repr_->emplace("full", full);
-    }
+    void operator()(SemanticTokensFullDelta full) { (*repr_)["full"] = full; }
   } v{repr_};
 
   std::visit(v, full.value());
@@ -10975,7 +10821,7 @@ auto SemanticTokensOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -10989,6 +10835,7 @@ SemanticTokensEdit::operator bool() const {
 auto SemanticTokensEdit::start() const -> long {
   auto& value = (*repr_)["start"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -10996,6 +10843,7 @@ auto SemanticTokensEdit::start() const -> long {
 auto SemanticTokensEdit::deleteCount() const -> long {
   auto& value = (*repr_)["deleteCount"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -11005,17 +10853,17 @@ auto SemanticTokensEdit::data() const -> std::optional<Vector<long>> {
 
   auto& value = (*repr_)["data"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<long>(value);
 }
 
 auto SemanticTokensEdit::start(long start) -> SemanticTokensEdit& {
-  repr_->emplace("start", std::move(start));
+  (*repr_)["start"] = std::move(start);
   return *this;
 }
 
 auto SemanticTokensEdit::deleteCount(long deleteCount) -> SemanticTokensEdit& {
-  repr_->emplace("deleteCount", std::move(deleteCount));
+  (*repr_)["deleteCount"] = std::move(deleteCount);
   return *this;
 }
 
@@ -11040,6 +10888,7 @@ auto LinkedEditingRangeOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -11050,7 +10899,7 @@ auto LinkedEditingRangeOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -11063,12 +10912,13 @@ FileCreate::operator bool() const {
 auto FileCreate::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto FileCreate::uri(std::string uri) -> FileCreate& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -11087,25 +10937,23 @@ auto TextDocumentEdit::textDocument() const
 }
 
 auto TextDocumentEdit::edits() const
-    -> Vector<std::variant<std::monostate, TextEdit, AnnotatedTextEdit,
-                           SnippetTextEdit>> {
+    -> Vector<std::variant<TextEdit, AnnotatedTextEdit, SnippetTextEdit>> {
   auto& value = (*repr_)["edits"];
 
-  assert(value.is_array());
-  return Vector<std::variant<std::monostate, TextEdit, AnnotatedTextEdit,
-                             SnippetTextEdit>>(value);
+  if (value.is_null()) value = json::array();
+  return Vector<std::variant<TextEdit, AnnotatedTextEdit, SnippetTextEdit>>(
+      value);
 }
 
 auto TextDocumentEdit::textDocument(
     OptionalVersionedTextDocumentIdentifier textDocument) -> TextDocumentEdit& {
-  repr_->emplace("textDocument", textDocument);
+  (*repr_)["textDocument"] = textDocument;
   return *this;
 }
 
 auto TextDocumentEdit::edits(
-    Vector<std::variant<std::monostate, TextEdit, AnnotatedTextEdit,
-                        SnippetTextEdit>>
-        edits) -> TextDocumentEdit& {
+    Vector<std::variant<TextEdit, AnnotatedTextEdit, SnippetTextEdit>> edits)
+    -> TextDocumentEdit& {
   lsp_runtime_error("TextDocumentEdit::edits: not implement yet");
   return *this;
 }
@@ -11121,6 +10969,7 @@ CreateFile::operator bool() const {
 auto CreateFile::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "create";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11128,6 +10977,7 @@ auto CreateFile::kind() const -> std::string {
 auto CreateFile::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11146,6 +10996,7 @@ auto CreateFile::annotationId() const
 
   auto& value = (*repr_)["annotationId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11156,7 +11007,7 @@ auto CreateFile::kind(std::string kind) -> CreateFile& {
 }
 
 auto CreateFile::uri(std::string uri) -> CreateFile& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -11166,7 +11017,7 @@ auto CreateFile::options(std::optional<CreateFileOptions> options)
     repr_->erase("options");
     return *this;
   }
-  repr_->emplace("options", options.value());
+  (*repr_)["options"] = options.value();
   return *this;
 }
 
@@ -11192,6 +11043,7 @@ RenameFile::operator bool() const {
 auto RenameFile::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "rename";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11199,6 +11051,7 @@ auto RenameFile::kind() const -> std::string {
 auto RenameFile::oldUri() const -> std::string {
   auto& value = (*repr_)["oldUri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11206,6 +11059,7 @@ auto RenameFile::oldUri() const -> std::string {
 auto RenameFile::newUri() const -> std::string {
   auto& value = (*repr_)["newUri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11224,6 +11078,7 @@ auto RenameFile::annotationId() const
 
   auto& value = (*repr_)["annotationId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11234,12 +11089,12 @@ auto RenameFile::kind(std::string kind) -> RenameFile& {
 }
 
 auto RenameFile::oldUri(std::string oldUri) -> RenameFile& {
-  repr_->emplace("oldUri", std::move(oldUri));
+  (*repr_)["oldUri"] = std::move(oldUri);
   return *this;
 }
 
 auto RenameFile::newUri(std::string newUri) -> RenameFile& {
-  repr_->emplace("newUri", std::move(newUri));
+  (*repr_)["newUri"] = std::move(newUri);
   return *this;
 }
 
@@ -11249,7 +11104,7 @@ auto RenameFile::options(std::optional<RenameFileOptions> options)
     repr_->erase("options");
     return *this;
   }
-  repr_->emplace("options", options.value());
+  (*repr_)["options"] = options.value();
   return *this;
 }
 
@@ -11274,6 +11129,7 @@ DeleteFile::operator bool() const {
 auto DeleteFile::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "delete";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11281,6 +11137,7 @@ auto DeleteFile::kind() const -> std::string {
 auto DeleteFile::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11299,6 +11156,7 @@ auto DeleteFile::annotationId() const
 
   auto& value = (*repr_)["annotationId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11309,7 +11167,7 @@ auto DeleteFile::kind(std::string kind) -> DeleteFile& {
 }
 
 auto DeleteFile::uri(std::string uri) -> DeleteFile& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -11319,7 +11177,7 @@ auto DeleteFile::options(std::optional<DeleteFileOptions> options)
     repr_->erase("options");
     return *this;
   }
-  repr_->emplace("options", options.value());
+  (*repr_)["options"] = options.value();
   return *this;
 }
 
@@ -11342,6 +11200,7 @@ ChangeAnnotation::operator bool() const {
 auto ChangeAnnotation::label() const -> std::string {
   auto& value = (*repr_)["label"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11351,6 +11210,7 @@ auto ChangeAnnotation::needsConfirmation() const -> std::optional<bool> {
 
   auto& value = (*repr_)["needsConfirmation"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -11360,12 +11220,13 @@ auto ChangeAnnotation::description() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["description"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto ChangeAnnotation::label(std::string label) -> ChangeAnnotation& {
-  repr_->emplace("label", std::move(label));
+  (*repr_)["label"] = std::move(label);
   return *this;
 }
 
@@ -11375,7 +11236,7 @@ auto ChangeAnnotation::needsConfirmation(std::optional<bool> needsConfirmation)
     repr_->erase("needsConfirmation");
     return *this;
   }
-  repr_->emplace("needsConfirmation", std::move(needsConfirmation.value()));
+  (*repr_)["needsConfirmation"] = std::move(needsConfirmation.value());
   return *this;
 }
 
@@ -11385,7 +11246,7 @@ auto ChangeAnnotation::description(std::optional<std::string> description)
     repr_->erase("description");
     return *this;
   }
-  repr_->emplace("description", std::move(description.value()));
+  (*repr_)["description"] = std::move(description.value());
   return *this;
 }
 
@@ -11400,6 +11261,7 @@ auto FileOperationFilter::scheme() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["scheme"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11416,13 +11278,13 @@ auto FileOperationFilter::scheme(std::optional<std::string> scheme)
     repr_->erase("scheme");
     return *this;
   }
-  repr_->emplace("scheme", std::move(scheme.value()));
+  (*repr_)["scheme"] = std::move(scheme.value());
   return *this;
 }
 
 auto FileOperationFilter::pattern(FileOperationPattern pattern)
     -> FileOperationFilter& {
-  repr_->emplace("pattern", pattern);
+  (*repr_)["pattern"] = pattern;
   return *this;
 }
 
@@ -11436,6 +11298,7 @@ FileRename::operator bool() const {
 auto FileRename::oldUri() const -> std::string {
   auto& value = (*repr_)["oldUri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11443,17 +11306,18 @@ auto FileRename::oldUri() const -> std::string {
 auto FileRename::newUri() const -> std::string {
   auto& value = (*repr_)["newUri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto FileRename::oldUri(std::string oldUri) -> FileRename& {
-  repr_->emplace("oldUri", std::move(oldUri));
+  (*repr_)["oldUri"] = std::move(oldUri);
   return *this;
 }
 
 auto FileRename::newUri(std::string newUri) -> FileRename& {
-  repr_->emplace("newUri", std::move(newUri));
+  (*repr_)["newUri"] = std::move(newUri);
   return *this;
 }
 
@@ -11466,12 +11330,13 @@ FileDelete::operator bool() const {
 auto FileDelete::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto FileDelete::uri(std::string uri) -> FileDelete& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -11485,6 +11350,7 @@ auto MonikerOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -11495,7 +11361,7 @@ auto MonikerOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -11509,6 +11375,7 @@ auto TypeHierarchyOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -11519,7 +11386,7 @@ auto TypeHierarchyOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -11533,6 +11400,7 @@ InlineValueContext::operator bool() const {
 auto InlineValueContext::frameId() const -> int {
   auto& value = (*repr_)["frameId"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<int>();
 }
@@ -11544,13 +11412,13 @@ auto InlineValueContext::stoppedLocation() const -> Range {
 }
 
 auto InlineValueContext::frameId(int frameId) -> InlineValueContext& {
-  repr_->emplace("frameId", std::move(frameId));
+  (*repr_)["frameId"] = std::move(frameId);
   return *this;
 }
 
 auto InlineValueContext::stoppedLocation(Range stoppedLocation)
     -> InlineValueContext& {
-  repr_->emplace("stoppedLocation", stoppedLocation);
+  (*repr_)["stoppedLocation"] = stoppedLocation;
   return *this;
 }
 
@@ -11570,17 +11438,18 @@ auto InlineValueText::range() const -> Range {
 auto InlineValueText::text() const -> std::string {
   auto& value = (*repr_)["text"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto InlineValueText::range(Range range) -> InlineValueText& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto InlineValueText::text(std::string text) -> InlineValueText& {
-  repr_->emplace("text", std::move(text));
+  (*repr_)["text"] = std::move(text);
   return *this;
 }
 
@@ -11603,6 +11472,7 @@ auto InlineValueVariableLookup::variableName() const
 
   auto& value = (*repr_)["variableName"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11610,13 +11480,14 @@ auto InlineValueVariableLookup::variableName() const
 auto InlineValueVariableLookup::caseSensitiveLookup() const -> bool {
   auto& value = (*repr_)["caseSensitiveLookup"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto InlineValueVariableLookup::range(Range range)
     -> InlineValueVariableLookup& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -11626,13 +11497,13 @@ auto InlineValueVariableLookup::variableName(
     repr_->erase("variableName");
     return *this;
   }
-  repr_->emplace("variableName", std::move(variableName.value()));
+  (*repr_)["variableName"] = std::move(variableName.value());
   return *this;
 }
 
 auto InlineValueVariableLookup::caseSensitiveLookup(bool caseSensitiveLookup)
     -> InlineValueVariableLookup& {
-  repr_->emplace("caseSensitiveLookup", std::move(caseSensitiveLookup));
+  (*repr_)["caseSensitiveLookup"] = std::move(caseSensitiveLookup);
   return *this;
 }
 
@@ -11654,13 +11525,14 @@ auto InlineValueEvaluatableExpression::expression() const
 
   auto& value = (*repr_)["expression"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto InlineValueEvaluatableExpression::range(Range range)
     -> InlineValueEvaluatableExpression& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -11671,7 +11543,7 @@ auto InlineValueEvaluatableExpression::expression(
     repr_->erase("expression");
     return *this;
   }
-  repr_->emplace("expression", std::move(expression.value()));
+  (*repr_)["expression"] = std::move(expression.value());
   return *this;
 }
 
@@ -11685,6 +11557,7 @@ auto InlineValueOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -11695,7 +11568,7 @@ auto InlineValueOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -11708,17 +11581,18 @@ InlayHintLabelPart::operator bool() const {
 auto InlayHintLabelPart::value() const -> std::string {
   auto& value = (*repr_)["value"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto InlayHintLabelPart::tooltip() const
-    -> std::optional<std::variant<std::monostate, std::string, MarkupContent>> {
+    -> std::optional<std::variant<std::string, MarkupContent>> {
   if (!repr_->contains("tooltip")) return std::nullopt;
 
   auto& value = (*repr_)["tooltip"];
 
-  std::variant<std::monostate, std::string, MarkupContent> result;
+  std::variant<std::string, MarkupContent> result;
 
   details::try_emplace(result, value);
 
@@ -11742,34 +11616,26 @@ auto InlayHintLabelPart::command() const -> std::optional<Command> {
 }
 
 auto InlayHintLabelPart::value(std::string value) -> InlayHintLabelPart& {
-  repr_->emplace("value", std::move(value));
+  (*repr_)["value"] = std::move(value);
   return *this;
 }
 
 auto InlayHintLabelPart::tooltip(
-    std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-        tooltip) -> InlayHintLabelPart& {
+    std::optional<std::variant<std::string, MarkupContent>> tooltip)
+    -> InlayHintLabelPart& {
   if (!tooltip.has_value()) {
     repr_->erase("tooltip");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string tooltip) {
-      repr_->emplace("tooltip", std::move(tooltip));
+      (*repr_)["tooltip"] = std::move(tooltip);
     }
 
-    void operator()(MarkupContent tooltip) {
-      repr_->emplace("tooltip", tooltip);
-    }
+    void operator()(MarkupContent tooltip) { (*repr_)["tooltip"] = tooltip; }
   } v{repr_};
 
   std::visit(v, tooltip.value());
@@ -11783,7 +11649,7 @@ auto InlayHintLabelPart::location(std::optional<Location> location)
     repr_->erase("location");
     return *this;
   }
-  repr_->emplace("location", location.value());
+  (*repr_)["location"] = location.value();
   return *this;
 }
 
@@ -11793,7 +11659,7 @@ auto InlayHintLabelPart::command(std::optional<Command> command)
     repr_->erase("command");
     return *this;
   }
-  repr_->emplace("command", command.value());
+  (*repr_)["command"] = command.value();
   return *this;
 }
 
@@ -11813,6 +11679,7 @@ auto MarkupContent::kind() const -> MarkupKind {
 auto MarkupContent::value() const -> std::string {
   auto& value = (*repr_)["value"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11823,7 +11690,7 @@ auto MarkupContent::kind(MarkupKind kind) -> MarkupContent& {
 }
 
 auto MarkupContent::value(std::string value) -> MarkupContent& {
-  repr_->emplace("value", std::move(value));
+  (*repr_)["value"] = std::move(value);
   return *this;
 }
 
@@ -11837,6 +11704,7 @@ auto InlayHintOptions::resolveProvider() const -> std::optional<bool> {
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -11846,6 +11714,7 @@ auto InlayHintOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -11856,7 +11725,7 @@ auto InlayHintOptions::resolveProvider(std::optional<bool> resolveProvider)
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -11866,7 +11735,7 @@ auto InlayHintOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -11879,22 +11748,23 @@ RelatedFullDocumentDiagnosticReport::operator bool() const {
 }
 
 auto RelatedFullDocumentDiagnosticReport::relatedDocuments() const
-    -> std::optional<Map<
-        std::string, std::variant<std::monostate, FullDocumentDiagnosticReport,
-                                  UnchangedDocumentDiagnosticReport>>> {
+    -> std::optional<
+        Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                      UnchangedDocumentDiagnosticReport>>> {
   if (!repr_->contains("relatedDocuments")) return std::nullopt;
 
   auto& value = (*repr_)["relatedDocuments"];
 
-  assert(value.is_object());
-  return Map<std::string,
-             std::variant<std::monostate, FullDocumentDiagnosticReport,
-                          UnchangedDocumentDiagnosticReport>>(value);
+  if (value.is_null()) value = json::object();
+  return Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                       UnchangedDocumentDiagnosticReport>>(
+      value);
 }
 
 auto RelatedFullDocumentDiagnosticReport::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "full";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11905,6 +11775,7 @@ auto RelatedFullDocumentDiagnosticReport::resultId() const
 
   auto& value = (*repr_)["resultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11912,14 +11783,14 @@ auto RelatedFullDocumentDiagnosticReport::resultId() const
 auto RelatedFullDocumentDiagnosticReport::items() const -> Vector<Diagnostic> {
   auto& value = (*repr_)["items"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Diagnostic>(value);
 }
 
 auto RelatedFullDocumentDiagnosticReport::relatedDocuments(
-    std::optional<Map<std::string,
-                      std::variant<std::monostate, FullDocumentDiagnosticReport,
-                                   UnchangedDocumentDiagnosticReport>>>
+    std::optional<
+        Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                      UnchangedDocumentDiagnosticReport>>>
         relatedDocuments) -> RelatedFullDocumentDiagnosticReport& {
   if (!relatedDocuments.has_value()) {
     repr_->erase("relatedDocuments");
@@ -11945,7 +11816,7 @@ auto RelatedFullDocumentDiagnosticReport::resultId(
     repr_->erase("resultId");
     return *this;
   }
-  repr_->emplace("resultId", std::move(resultId.value()));
+  (*repr_)["resultId"] = std::move(resultId.value());
   return *this;
 }
 
@@ -11965,22 +11836,23 @@ RelatedUnchangedDocumentDiagnosticReport::operator bool() const {
 }
 
 auto RelatedUnchangedDocumentDiagnosticReport::relatedDocuments() const
-    -> std::optional<Map<
-        std::string, std::variant<std::monostate, FullDocumentDiagnosticReport,
-                                  UnchangedDocumentDiagnosticReport>>> {
+    -> std::optional<
+        Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                      UnchangedDocumentDiagnosticReport>>> {
   if (!repr_->contains("relatedDocuments")) return std::nullopt;
 
   auto& value = (*repr_)["relatedDocuments"];
 
-  assert(value.is_object());
-  return Map<std::string,
-             std::variant<std::monostate, FullDocumentDiagnosticReport,
-                          UnchangedDocumentDiagnosticReport>>(value);
+  if (value.is_null()) value = json::object();
+  return Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                       UnchangedDocumentDiagnosticReport>>(
+      value);
 }
 
 auto RelatedUnchangedDocumentDiagnosticReport::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "unchanged";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -11988,14 +11860,15 @@ auto RelatedUnchangedDocumentDiagnosticReport::kind() const -> std::string {
 auto RelatedUnchangedDocumentDiagnosticReport::resultId() const -> std::string {
   auto& value = (*repr_)["resultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto RelatedUnchangedDocumentDiagnosticReport::relatedDocuments(
-    std::optional<Map<std::string,
-                      std::variant<std::monostate, FullDocumentDiagnosticReport,
-                                   UnchangedDocumentDiagnosticReport>>>
+    std::optional<
+        Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                      UnchangedDocumentDiagnosticReport>>>
         relatedDocuments) -> RelatedUnchangedDocumentDiagnosticReport& {
   if (!relatedDocuments.has_value()) {
     repr_->erase("relatedDocuments");
@@ -12016,7 +11889,7 @@ auto RelatedUnchangedDocumentDiagnosticReport::kind(std::string kind)
 
 auto RelatedUnchangedDocumentDiagnosticReport::resultId(std::string resultId)
     -> RelatedUnchangedDocumentDiagnosticReport& {
-  repr_->emplace("resultId", std::move(resultId));
+  (*repr_)["resultId"] = std::move(resultId);
   return *this;
 }
 
@@ -12031,6 +11904,7 @@ FullDocumentDiagnosticReport::operator bool() const {
 auto FullDocumentDiagnosticReport::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "full";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12041,6 +11915,7 @@ auto FullDocumentDiagnosticReport::resultId() const
 
   auto& value = (*repr_)["resultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12048,7 +11923,7 @@ auto FullDocumentDiagnosticReport::resultId() const
 auto FullDocumentDiagnosticReport::items() const -> Vector<Diagnostic> {
   auto& value = (*repr_)["items"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Diagnostic>(value);
 }
 
@@ -12064,7 +11939,7 @@ auto FullDocumentDiagnosticReport::resultId(std::optional<std::string> resultId)
     repr_->erase("resultId");
     return *this;
   }
-  repr_->emplace("resultId", std::move(resultId.value()));
+  (*repr_)["resultId"] = std::move(resultId.value());
   return *this;
 }
 
@@ -12085,6 +11960,7 @@ UnchangedDocumentDiagnosticReport::operator bool() const {
 auto UnchangedDocumentDiagnosticReport::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "unchanged";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12092,6 +11968,7 @@ auto UnchangedDocumentDiagnosticReport::kind() const -> std::string {
 auto UnchangedDocumentDiagnosticReport::resultId() const -> std::string {
   auto& value = (*repr_)["resultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12105,7 +11982,7 @@ auto UnchangedDocumentDiagnosticReport::kind(std::string kind)
 
 auto UnchangedDocumentDiagnosticReport::resultId(std::string resultId)
     -> UnchangedDocumentDiagnosticReport& {
-  repr_->emplace("resultId", std::move(resultId));
+  (*repr_)["resultId"] = std::move(resultId);
   return *this;
 }
 
@@ -12121,6 +11998,7 @@ auto DiagnosticOptions::identifier() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["identifier"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12128,6 +12006,7 @@ auto DiagnosticOptions::identifier() const -> std::optional<std::string> {
 auto DiagnosticOptions::interFileDependencies() const -> bool {
   auto& value = (*repr_)["interFileDependencies"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -12135,6 +12014,7 @@ auto DiagnosticOptions::interFileDependencies() const -> bool {
 auto DiagnosticOptions::workspaceDiagnostics() const -> bool {
   auto& value = (*repr_)["workspaceDiagnostics"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -12144,6 +12024,7 @@ auto DiagnosticOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -12154,19 +12035,19 @@ auto DiagnosticOptions::identifier(std::optional<std::string> identifier)
     repr_->erase("identifier");
     return *this;
   }
-  repr_->emplace("identifier", std::move(identifier.value()));
+  (*repr_)["identifier"] = std::move(identifier.value());
   return *this;
 }
 
 auto DiagnosticOptions::interFileDependencies(bool interFileDependencies)
     -> DiagnosticOptions& {
-  repr_->emplace("interFileDependencies", std::move(interFileDependencies));
+  (*repr_)["interFileDependencies"] = std::move(interFileDependencies);
   return *this;
 }
 
 auto DiagnosticOptions::workspaceDiagnostics(bool workspaceDiagnostics)
     -> DiagnosticOptions& {
-  repr_->emplace("workspaceDiagnostics", std::move(workspaceDiagnostics));
+  (*repr_)["workspaceDiagnostics"] = std::move(workspaceDiagnostics);
   return *this;
 }
 
@@ -12176,7 +12057,7 @@ auto DiagnosticOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -12190,6 +12071,7 @@ PreviousResultId::operator bool() const {
 auto PreviousResultId::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12197,17 +12079,18 @@ auto PreviousResultId::uri() const -> std::string {
 auto PreviousResultId::value() const -> std::string {
   auto& value = (*repr_)["value"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto PreviousResultId::uri(std::string uri) -> PreviousResultId& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto PreviousResultId::value(std::string value) -> PreviousResultId& {
-  repr_->emplace("value", std::move(value));
+  (*repr_)["value"] = std::move(value);
   return *this;
 }
 
@@ -12223,6 +12106,7 @@ NotebookDocument::operator bool() const {
 auto NotebookDocument::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12230,6 +12114,7 @@ auto NotebookDocument::uri() const -> std::string {
 auto NotebookDocument::notebookType() const -> std::string {
   auto& value = (*repr_)["notebookType"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12237,6 +12122,7 @@ auto NotebookDocument::notebookType() const -> std::string {
 auto NotebookDocument::version() const -> int {
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<int>();
 }
@@ -12253,23 +12139,23 @@ auto NotebookDocument::metadata() const -> std::optional<LSPObject> {
 auto NotebookDocument::cells() const -> Vector<NotebookCell> {
   auto& value = (*repr_)["cells"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<NotebookCell>(value);
 }
 
 auto NotebookDocument::uri(std::string uri) -> NotebookDocument& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto NotebookDocument::notebookType(std::string notebookType)
     -> NotebookDocument& {
-  repr_->emplace("notebookType", std::move(notebookType));
+  (*repr_)["notebookType"] = std::move(notebookType);
   return *this;
 }
 
 auto NotebookDocument::version(int version) -> NotebookDocument& {
-  repr_->emplace("version", std::move(version));
+  (*repr_)["version"] = std::move(version);
   return *this;
 }
 
@@ -12300,6 +12186,7 @@ TextDocumentItem::operator bool() const {
 auto TextDocumentItem::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12313,6 +12200,7 @@ auto TextDocumentItem::languageId() const -> LanguageKind {
 auto TextDocumentItem::version() const -> int {
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<int>();
 }
@@ -12320,12 +12208,13 @@ auto TextDocumentItem::version() const -> int {
 auto TextDocumentItem::text() const -> std::string {
   auto& value = (*repr_)["text"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TextDocumentItem::uri(std::string uri) -> TextDocumentItem& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -12336,12 +12225,12 @@ auto TextDocumentItem::languageId(LanguageKind languageId)
 }
 
 auto TextDocumentItem::version(int version) -> TextDocumentItem& {
-  repr_->emplace("version", std::move(version));
+  (*repr_)["version"] = std::move(version);
   return *this;
 }
 
 auto TextDocumentItem::text(std::string text) -> TextDocumentItem& {
-  repr_->emplace("text", std::move(text));
+  (*repr_)["text"] = std::move(text);
   return *this;
 }
 
@@ -12352,12 +12241,12 @@ NotebookDocumentSyncOptions::operator bool() const {
 }
 
 auto NotebookDocumentSyncOptions::notebookSelector() const
-    -> Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
+    -> Vector<std::variant<NotebookDocumentFilterWithNotebook,
                            NotebookDocumentFilterWithCells>> {
   auto& value = (*repr_)["notebookSelector"];
 
-  assert(value.is_array());
-  return Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
+  if (value.is_null()) value = json::array();
+  return Vector<std::variant<NotebookDocumentFilterWithNotebook,
                              NotebookDocumentFilterWithCells>>(value);
 }
 
@@ -12366,12 +12255,13 @@ auto NotebookDocumentSyncOptions::save() const -> std::optional<bool> {
 
   auto& value = (*repr_)["save"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto NotebookDocumentSyncOptions::notebookSelector(
-    Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
+    Vector<std::variant<NotebookDocumentFilterWithNotebook,
                         NotebookDocumentFilterWithCells>>
         notebookSelector) -> NotebookDocumentSyncOptions& {
   lsp_runtime_error(
@@ -12385,7 +12275,7 @@ auto NotebookDocumentSyncOptions::save(std::optional<bool> save)
     repr_->erase("save");
     return *this;
   }
-  repr_->emplace("save", std::move(save.value()));
+  (*repr_)["save"] = std::move(save.value());
   return *this;
 }
 
@@ -12399,6 +12289,7 @@ VersionedNotebookDocumentIdentifier::operator bool() const {
 auto VersionedNotebookDocumentIdentifier::version() const -> int {
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<int>();
 }
@@ -12406,19 +12297,20 @@ auto VersionedNotebookDocumentIdentifier::version() const -> int {
 auto VersionedNotebookDocumentIdentifier::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto VersionedNotebookDocumentIdentifier::version(int version)
     -> VersionedNotebookDocumentIdentifier& {
-  repr_->emplace("version", std::move(version));
+  (*repr_)["version"] = std::move(version);
   return *this;
 }
 
 auto VersionedNotebookDocumentIdentifier::uri(std::string uri)
     -> VersionedNotebookDocumentIdentifier& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -12462,7 +12354,7 @@ auto NotebookDocumentChangeEvent::cells(
     repr_->erase("cells");
     return *this;
   }
-  repr_->emplace("cells", cells.value());
+  (*repr_)["cells"] = cells.value();
   return *this;
 }
 
@@ -12475,13 +12367,14 @@ NotebookDocumentIdentifier::operator bool() const {
 auto NotebookDocumentIdentifier::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto NotebookDocumentIdentifier::uri(std::string uri)
     -> NotebookDocumentIdentifier& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -12509,7 +12402,7 @@ auto InlineCompletionContext::selectedCompletionInfo() const
 
 auto InlineCompletionContext::triggerKind(
     InlineCompletionTriggerKind triggerKind) -> InlineCompletionContext& {
-  repr_->emplace("triggerKind", static_cast<long>(triggerKind));
+  (*repr_)["triggerKind"] = static_cast<long>(triggerKind);
   return *this;
 }
 
@@ -12520,7 +12413,7 @@ auto InlineCompletionContext::selectedCompletionInfo(
     repr_->erase("selectedCompletionInfo");
     return *this;
   }
-  repr_->emplace("selectedCompletionInfo", selectedCompletionInfo.value());
+  (*repr_)["selectedCompletionInfo"] = selectedCompletionInfo.value();
   return *this;
 }
 
@@ -12535,6 +12428,7 @@ StringValue::operator bool() const {
 auto StringValue::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "snippet";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12542,6 +12436,7 @@ auto StringValue::kind() const -> std::string {
 auto StringValue::value() const -> std::string {
   auto& value = (*repr_)["value"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12552,7 +12447,7 @@ auto StringValue::kind(std::string kind) -> StringValue& {
 }
 
 auto StringValue::value(std::string value) -> StringValue& {
-  repr_->emplace("value", std::move(value));
+  (*repr_)["value"] = std::move(value);
   return *this;
 }
 
@@ -12566,6 +12461,7 @@ auto InlineCompletionOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -12576,7 +12472,7 @@ auto InlineCompletionOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -12589,7 +12485,7 @@ TextDocumentContentOptions::operator bool() const {
 auto TextDocumentContentOptions::schemes() const -> Vector<std::string> {
   auto& value = (*repr_)["schemes"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -12609,6 +12505,7 @@ Registration::operator bool() const {
 auto Registration::id() const -> std::string {
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12616,6 +12513,7 @@ auto Registration::id() const -> std::string {
 auto Registration::method() const -> std::string {
   auto& value = (*repr_)["method"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12630,12 +12528,12 @@ auto Registration::registerOptions() const -> std::optional<LSPAny> {
 }
 
 auto Registration::id(std::string id) -> Registration& {
-  repr_->emplace("id", std::move(id));
+  (*repr_)["id"] = std::move(id);
   return *this;
 }
 
 auto Registration::method(std::string method) -> Registration& {
-  repr_->emplace("method", std::move(method));
+  (*repr_)["method"] = std::move(method);
   return *this;
 }
 
@@ -12659,6 +12557,7 @@ Unregistration::operator bool() const {
 auto Unregistration::id() const -> std::string {
   auto& value = (*repr_)["id"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -12666,17 +12565,18 @@ auto Unregistration::id() const -> std::string {
 auto Unregistration::method() const -> std::string {
   auto& value = (*repr_)["method"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto Unregistration::id(std::string id) -> Unregistration& {
-  repr_->emplace("id", std::move(id));
+  (*repr_)["id"] = std::move(id);
   return *this;
 }
 
 auto Unregistration::method(std::string method) -> Unregistration& {
-  repr_->emplace("method", std::move(method));
+  (*repr_)["method"] = std::move(method);
   return *this;
 }
 
@@ -12688,11 +12588,10 @@ _InitializeParams::operator bool() const {
   return true;
 }
 
-auto _InitializeParams::processId() const
-    -> std::variant<std::monostate, int, std::nullptr_t> {
+auto _InitializeParams::processId() const -> std::variant<int, std::nullptr_t> {
   auto& value = (*repr_)["processId"];
 
-  std::variant<std::monostate, int, std::nullptr_t> result;
+  std::variant<int, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -12712,17 +12611,18 @@ auto _InitializeParams::locale() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["locale"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
-auto _InitializeParams::rootPath() const -> std::optional<
-    std::variant<std::monostate, std::string, std::nullptr_t>> {
+auto _InitializeParams::rootPath() const
+    -> std::optional<std::variant<std::string, std::nullptr_t>> {
   if (!repr_->contains("rootPath")) return std::nullopt;
 
   auto& value = (*repr_)["rootPath"];
 
-  std::variant<std::monostate, std::string, std::nullptr_t> result;
+  std::variant<std::string, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -12730,10 +12630,10 @@ auto _InitializeParams::rootPath() const -> std::optional<
 }
 
 auto _InitializeParams::rootUri() const
-    -> std::variant<std::monostate, std::string, std::nullptr_t> {
+    -> std::variant<std::string, std::nullptr_t> {
   auto& value = (*repr_)["rootUri"];
 
-  std::variant<std::monostate, std::string, std::nullptr_t> result;
+  std::variant<std::string, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -12775,24 +12675,17 @@ auto _InitializeParams::workDoneToken() const -> std::optional<ProgressToken> {
   return result;
 }
 
-auto _InitializeParams::processId(
-    std::variant<std::monostate, int, std::nullptr_t> processId)
+auto _InitializeParams::processId(std::variant<int, std::nullptr_t> processId)
     -> _InitializeParams& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(int processId) {
-      repr_->emplace("processId", std::move(processId));
+      (*repr_)["processId"] = std::move(processId);
     }
 
     void operator()(std::nullptr_t processId) {
-      repr_->emplace("processId", std::move(processId));
+      (*repr_)["processId"] = std::move(processId);
     }
   } v{repr_};
 
@@ -12807,7 +12700,7 @@ auto _InitializeParams::clientInfo(std::optional<ClientInfo> clientInfo)
     repr_->erase("clientInfo");
     return *this;
   }
-  repr_->emplace("clientInfo", clientInfo.value());
+  (*repr_)["clientInfo"] = clientInfo.value();
   return *this;
 }
 
@@ -12817,33 +12710,27 @@ auto _InitializeParams::locale(std::optional<std::string> locale)
     repr_->erase("locale");
     return *this;
   }
-  repr_->emplace("locale", std::move(locale.value()));
+  (*repr_)["locale"] = std::move(locale.value());
   return *this;
 }
 
 auto _InitializeParams::rootPath(
-    std::optional<std::variant<std::monostate, std::string, std::nullptr_t>>
-        rootPath) -> _InitializeParams& {
+    std::optional<std::variant<std::string, std::nullptr_t>> rootPath)
+    -> _InitializeParams& {
   if (!rootPath.has_value()) {
     repr_->erase("rootPath");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string rootPath) {
-      repr_->emplace("rootPath", std::move(rootPath));
+      (*repr_)["rootPath"] = std::move(rootPath);
     }
 
     void operator()(std::nullptr_t rootPath) {
-      repr_->emplace("rootPath", std::move(rootPath));
+      (*repr_)["rootPath"] = std::move(rootPath);
     }
   } v{repr_};
 
@@ -12853,23 +12740,16 @@ auto _InitializeParams::rootPath(
 }
 
 auto _InitializeParams::rootUri(
-    std::variant<std::monostate, std::string, std::nullptr_t> rootUri)
-    -> _InitializeParams& {
-  // or type
-
+    std::variant<std::string, std::nullptr_t> rootUri) -> _InitializeParams& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string rootUri) {
-      repr_->emplace("rootUri", std::move(rootUri));
+      (*repr_)["rootUri"] = std::move(rootUri);
     }
 
     void operator()(std::nullptr_t rootUri) {
-      repr_->emplace("rootUri", std::move(rootUri));
+      (*repr_)["rootUri"] = std::move(rootUri);
     }
   } v{repr_};
 
@@ -12880,7 +12760,7 @@ auto _InitializeParams::rootUri(
 
 auto _InitializeParams::capabilities(ClientCapabilities capabilities)
     -> _InitializeParams& {
-  repr_->emplace("capabilities", capabilities);
+  (*repr_)["capabilities"] = capabilities;
   return *this;
 }
 
@@ -12921,13 +12801,12 @@ WorkspaceFoldersInitializeParams::operator bool() const {
 }
 
 auto WorkspaceFoldersInitializeParams::workspaceFolders() const
-    -> std::optional<
-        std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t>> {
+    -> std::optional<std::variant<Vector<WorkspaceFolder>, std::nullptr_t>> {
   if (!repr_->contains("workspaceFolders")) return std::nullopt;
 
   auto& value = (*repr_)["workspaceFolders"];
 
-  std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t> result;
+  std::variant<Vector<WorkspaceFolder>, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -12935,23 +12814,16 @@ auto WorkspaceFoldersInitializeParams::workspaceFolders() const
 }
 
 auto WorkspaceFoldersInitializeParams::workspaceFolders(
-    std::optional<
-        std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t>>
+    std::optional<std::variant<Vector<WorkspaceFolder>, std::nullptr_t>>
         workspaceFolders) -> WorkspaceFoldersInitializeParams& {
   if (!workspaceFolders.has_value()) {
     repr_->erase("workspaceFolders");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(Vector<WorkspaceFolder> workspaceFolders) {
       lsp_runtime_error(
           "WorkspaceFoldersInitializeParams::workspaceFolders: not implement "
@@ -12959,7 +12831,7 @@ auto WorkspaceFoldersInitializeParams::workspaceFolders(
     }
 
     void operator()(std::nullptr_t workspaceFolders) {
-      repr_->emplace("workspaceFolders", std::move(workspaceFolders));
+      (*repr_)["workspaceFolders"] = std::move(workspaceFolders);
     }
   } v{repr_};
 
@@ -12982,15 +12854,13 @@ auto ServerCapabilities::positionEncoding() const
   lsp_runtime_error("ServerCapabilities::positionEncoding: not implement yet");
 }
 
-auto ServerCapabilities::textDocumentSync() const
-    -> std::optional<std::variant<std::monostate, TextDocumentSyncOptions,
-                                  TextDocumentSyncKind>> {
+auto ServerCapabilities::textDocumentSync() const -> std::optional<
+    std::variant<TextDocumentSyncOptions, TextDocumentSyncKind>> {
   if (!repr_->contains("textDocumentSync")) return std::nullopt;
 
   auto& value = (*repr_)["textDocumentSync"];
 
-  std::variant<std::monostate, TextDocumentSyncOptions, TextDocumentSyncKind>
-      result;
+  std::variant<TextDocumentSyncOptions, TextDocumentSyncKind> result;
 
   details::try_emplace(result, value);
 
@@ -12998,13 +12868,13 @@ auto ServerCapabilities::textDocumentSync() const
 }
 
 auto ServerCapabilities::notebookDocumentSync() const
-    -> std::optional<std::variant<std::monostate, NotebookDocumentSyncOptions,
+    -> std::optional<std::variant<NotebookDocumentSyncOptions,
                                   NotebookDocumentSyncRegistrationOptions>> {
   if (!repr_->contains("notebookDocumentSync")) return std::nullopt;
 
   auto& value = (*repr_)["notebookDocumentSync"];
 
-  std::variant<std::monostate, NotebookDocumentSyncOptions,
+  std::variant<NotebookDocumentSyncOptions,
                NotebookDocumentSyncRegistrationOptions>
       result;
 
@@ -13023,12 +12893,12 @@ auto ServerCapabilities::completionProvider() const
 }
 
 auto ServerCapabilities::hoverProvider() const
-    -> std::optional<std::variant<std::monostate, bool, HoverOptions>> {
+    -> std::optional<std::variant<bool, HoverOptions>> {
   if (!repr_->contains("hoverProvider")) return std::nullopt;
 
   auto& value = (*repr_)["hoverProvider"];
 
-  std::variant<std::monostate, bool, HoverOptions> result;
+  std::variant<bool, HoverOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13044,16 +12914,13 @@ auto ServerCapabilities::signatureHelpProvider() const
   return SignatureHelpOptions(value);
 }
 
-auto ServerCapabilities::declarationProvider() const
-    -> std::optional<std::variant<std::monostate, bool, DeclarationOptions,
-                                  DeclarationRegistrationOptions>> {
+auto ServerCapabilities::declarationProvider() const -> std::optional<
+    std::variant<bool, DeclarationOptions, DeclarationRegistrationOptions>> {
   if (!repr_->contains("declarationProvider")) return std::nullopt;
 
   auto& value = (*repr_)["declarationProvider"];
 
-  std::variant<std::monostate, bool, DeclarationOptions,
-               DeclarationRegistrationOptions>
-      result;
+  std::variant<bool, DeclarationOptions, DeclarationRegistrationOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13061,12 +12928,12 @@ auto ServerCapabilities::declarationProvider() const
 }
 
 auto ServerCapabilities::definitionProvider() const
-    -> std::optional<std::variant<std::monostate, bool, DefinitionOptions>> {
+    -> std::optional<std::variant<bool, DefinitionOptions>> {
   if (!repr_->contains("definitionProvider")) return std::nullopt;
 
   auto& value = (*repr_)["definitionProvider"];
 
-  std::variant<std::monostate, bool, DefinitionOptions> result;
+  std::variant<bool, DefinitionOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13074,14 +12941,13 @@ auto ServerCapabilities::definitionProvider() const
 }
 
 auto ServerCapabilities::typeDefinitionProvider() const
-    -> std::optional<std::variant<std::monostate, bool, TypeDefinitionOptions,
+    -> std::optional<std::variant<bool, TypeDefinitionOptions,
                                   TypeDefinitionRegistrationOptions>> {
   if (!repr_->contains("typeDefinitionProvider")) return std::nullopt;
 
   auto& value = (*repr_)["typeDefinitionProvider"];
 
-  std::variant<std::monostate, bool, TypeDefinitionOptions,
-               TypeDefinitionRegistrationOptions>
+  std::variant<bool, TypeDefinitionOptions, TypeDefinitionRegistrationOptions>
       result;
 
   details::try_emplace(result, value);
@@ -13090,14 +12956,13 @@ auto ServerCapabilities::typeDefinitionProvider() const
 }
 
 auto ServerCapabilities::implementationProvider() const
-    -> std::optional<std::variant<std::monostate, bool, ImplementationOptions,
+    -> std::optional<std::variant<bool, ImplementationOptions,
                                   ImplementationRegistrationOptions>> {
   if (!repr_->contains("implementationProvider")) return std::nullopt;
 
   auto& value = (*repr_)["implementationProvider"];
 
-  std::variant<std::monostate, bool, ImplementationOptions,
-               ImplementationRegistrationOptions>
+  std::variant<bool, ImplementationOptions, ImplementationRegistrationOptions>
       result;
 
   details::try_emplace(result, value);
@@ -13106,38 +12971,38 @@ auto ServerCapabilities::implementationProvider() const
 }
 
 auto ServerCapabilities::referencesProvider() const
-    -> std::optional<std::variant<std::monostate, bool, ReferenceOptions>> {
+    -> std::optional<std::variant<bool, ReferenceOptions>> {
   if (!repr_->contains("referencesProvider")) return std::nullopt;
 
   auto& value = (*repr_)["referencesProvider"];
 
-  std::variant<std::monostate, bool, ReferenceOptions> result;
+  std::variant<bool, ReferenceOptions> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ServerCapabilities::documentHighlightProvider() const -> std::optional<
-    std::variant<std::monostate, bool, DocumentHighlightOptions>> {
+auto ServerCapabilities::documentHighlightProvider() const
+    -> std::optional<std::variant<bool, DocumentHighlightOptions>> {
   if (!repr_->contains("documentHighlightProvider")) return std::nullopt;
 
   auto& value = (*repr_)["documentHighlightProvider"];
 
-  std::variant<std::monostate, bool, DocumentHighlightOptions> result;
+  std::variant<bool, DocumentHighlightOptions> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ServerCapabilities::documentSymbolProvider() const -> std::optional<
-    std::variant<std::monostate, bool, DocumentSymbolOptions>> {
+auto ServerCapabilities::documentSymbolProvider() const
+    -> std::optional<std::variant<bool, DocumentSymbolOptions>> {
   if (!repr_->contains("documentSymbolProvider")) return std::nullopt;
 
   auto& value = (*repr_)["documentSymbolProvider"];
 
-  std::variant<std::monostate, bool, DocumentSymbolOptions> result;
+  std::variant<bool, DocumentSymbolOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13145,12 +13010,12 @@ auto ServerCapabilities::documentSymbolProvider() const -> std::optional<
 }
 
 auto ServerCapabilities::codeActionProvider() const
-    -> std::optional<std::variant<std::monostate, bool, CodeActionOptions>> {
+    -> std::optional<std::variant<bool, CodeActionOptions>> {
   if (!repr_->contains("codeActionProvider")) return std::nullopt;
 
   auto& value = (*repr_)["codeActionProvider"];
 
-  std::variant<std::monostate, bool, CodeActionOptions> result;
+  std::variant<bool, CodeActionOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13176,14 +13041,13 @@ auto ServerCapabilities::documentLinkProvider() const
 }
 
 auto ServerCapabilities::colorProvider() const
-    -> std::optional<std::variant<std::monostate, bool, DocumentColorOptions,
+    -> std::optional<std::variant<bool, DocumentColorOptions,
                                   DocumentColorRegistrationOptions>> {
   if (!repr_->contains("colorProvider")) return std::nullopt;
 
   auto& value = (*repr_)["colorProvider"];
 
-  std::variant<std::monostate, bool, DocumentColorOptions,
-               DocumentColorRegistrationOptions>
+  std::variant<bool, DocumentColorOptions, DocumentColorRegistrationOptions>
       result;
 
   details::try_emplace(result, value);
@@ -13191,26 +13055,26 @@ auto ServerCapabilities::colorProvider() const
   return result;
 }
 
-auto ServerCapabilities::workspaceSymbolProvider() const -> std::optional<
-    std::variant<std::monostate, bool, WorkspaceSymbolOptions>> {
+auto ServerCapabilities::workspaceSymbolProvider() const
+    -> std::optional<std::variant<bool, WorkspaceSymbolOptions>> {
   if (!repr_->contains("workspaceSymbolProvider")) return std::nullopt;
 
   auto& value = (*repr_)["workspaceSymbolProvider"];
 
-  std::variant<std::monostate, bool, WorkspaceSymbolOptions> result;
+  std::variant<bool, WorkspaceSymbolOptions> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ServerCapabilities::documentFormattingProvider() const -> std::optional<
-    std::variant<std::monostate, bool, DocumentFormattingOptions>> {
+auto ServerCapabilities::documentFormattingProvider() const
+    -> std::optional<std::variant<bool, DocumentFormattingOptions>> {
   if (!repr_->contains("documentFormattingProvider")) return std::nullopt;
 
   auto& value = (*repr_)["documentFormattingProvider"];
 
-  std::variant<std::monostate, bool, DocumentFormattingOptions> result;
+  std::variant<bool, DocumentFormattingOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13218,13 +13082,12 @@ auto ServerCapabilities::documentFormattingProvider() const -> std::optional<
 }
 
 auto ServerCapabilities::documentRangeFormattingProvider() const
-    -> std::optional<
-        std::variant<std::monostate, bool, DocumentRangeFormattingOptions>> {
+    -> std::optional<std::variant<bool, DocumentRangeFormattingOptions>> {
   if (!repr_->contains("documentRangeFormattingProvider")) return std::nullopt;
 
   auto& value = (*repr_)["documentRangeFormattingProvider"];
 
-  std::variant<std::monostate, bool, DocumentRangeFormattingOptions> result;
+  std::variant<bool, DocumentRangeFormattingOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13241,27 +13104,25 @@ auto ServerCapabilities::documentOnTypeFormattingProvider() const
 }
 
 auto ServerCapabilities::renameProvider() const
-    -> std::optional<std::variant<std::monostate, bool, RenameOptions>> {
+    -> std::optional<std::variant<bool, RenameOptions>> {
   if (!repr_->contains("renameProvider")) return std::nullopt;
 
   auto& value = (*repr_)["renameProvider"];
 
-  std::variant<std::monostate, bool, RenameOptions> result;
+  std::variant<bool, RenameOptions> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ServerCapabilities::foldingRangeProvider() const
-    -> std::optional<std::variant<std::monostate, bool, FoldingRangeOptions,
-                                  FoldingRangeRegistrationOptions>> {
+auto ServerCapabilities::foldingRangeProvider() const -> std::optional<
+    std::variant<bool, FoldingRangeOptions, FoldingRangeRegistrationOptions>> {
   if (!repr_->contains("foldingRangeProvider")) return std::nullopt;
 
   auto& value = (*repr_)["foldingRangeProvider"];
 
-  std::variant<std::monostate, bool, FoldingRangeOptions,
-               FoldingRangeRegistrationOptions>
+  std::variant<bool, FoldingRangeOptions, FoldingRangeRegistrationOptions>
       result;
 
   details::try_emplace(result, value);
@@ -13270,14 +13131,13 @@ auto ServerCapabilities::foldingRangeProvider() const
 }
 
 auto ServerCapabilities::selectionRangeProvider() const
-    -> std::optional<std::variant<std::monostate, bool, SelectionRangeOptions,
+    -> std::optional<std::variant<bool, SelectionRangeOptions,
                                   SelectionRangeRegistrationOptions>> {
   if (!repr_->contains("selectionRangeProvider")) return std::nullopt;
 
   auto& value = (*repr_)["selectionRangeProvider"];
 
-  std::variant<std::monostate, bool, SelectionRangeOptions,
-               SelectionRangeRegistrationOptions>
+  std::variant<bool, SelectionRangeOptions, SelectionRangeRegistrationOptions>
       result;
 
   details::try_emplace(result, value);
@@ -13295,14 +13155,13 @@ auto ServerCapabilities::executeCommandProvider() const
 }
 
 auto ServerCapabilities::callHierarchyProvider() const
-    -> std::optional<std::variant<std::monostate, bool, CallHierarchyOptions,
+    -> std::optional<std::variant<bool, CallHierarchyOptions,
                                   CallHierarchyRegistrationOptions>> {
   if (!repr_->contains("callHierarchyProvider")) return std::nullopt;
 
   auto& value = (*repr_)["callHierarchyProvider"];
 
-  std::variant<std::monostate, bool, CallHierarchyOptions,
-               CallHierarchyRegistrationOptions>
+  std::variant<bool, CallHierarchyOptions, CallHierarchyRegistrationOptions>
       result;
 
   details::try_emplace(result, value);
@@ -13310,14 +13169,14 @@ auto ServerCapabilities::callHierarchyProvider() const
   return result;
 }
 
-auto ServerCapabilities::linkedEditingRangeProvider() const -> std::optional<
-    std::variant<std::monostate, bool, LinkedEditingRangeOptions,
-                 LinkedEditingRangeRegistrationOptions>> {
+auto ServerCapabilities::linkedEditingRangeProvider() const
+    -> std::optional<std::variant<bool, LinkedEditingRangeOptions,
+                                  LinkedEditingRangeRegistrationOptions>> {
   if (!repr_->contains("linkedEditingRangeProvider")) return std::nullopt;
 
   auto& value = (*repr_)["linkedEditingRangeProvider"];
 
-  std::variant<std::monostate, bool, LinkedEditingRangeOptions,
+  std::variant<bool, LinkedEditingRangeOptions,
                LinkedEditingRangeRegistrationOptions>
       result;
 
@@ -13326,31 +13185,26 @@ auto ServerCapabilities::linkedEditingRangeProvider() const -> std::optional<
   return result;
 }
 
-auto ServerCapabilities::semanticTokensProvider() const
-    -> std::optional<std::variant<std::monostate, SemanticTokensOptions,
-                                  SemanticTokensRegistrationOptions>> {
+auto ServerCapabilities::semanticTokensProvider() const -> std::optional<
+    std::variant<SemanticTokensOptions, SemanticTokensRegistrationOptions>> {
   if (!repr_->contains("semanticTokensProvider")) return std::nullopt;
 
   auto& value = (*repr_)["semanticTokensProvider"];
 
-  std::variant<std::monostate, SemanticTokensOptions,
-               SemanticTokensRegistrationOptions>
-      result;
+  std::variant<SemanticTokensOptions, SemanticTokensRegistrationOptions> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ServerCapabilities::monikerProvider() const
-    -> std::optional<std::variant<std::monostate, bool, MonikerOptions,
-                                  MonikerRegistrationOptions>> {
+auto ServerCapabilities::monikerProvider() const -> std::optional<
+    std::variant<bool, MonikerOptions, MonikerRegistrationOptions>> {
   if (!repr_->contains("monikerProvider")) return std::nullopt;
 
   auto& value = (*repr_)["monikerProvider"];
 
-  std::variant<std::monostate, bool, MonikerOptions, MonikerRegistrationOptions>
-      result;
+  std::variant<bool, MonikerOptions, MonikerRegistrationOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13358,14 +13212,13 @@ auto ServerCapabilities::monikerProvider() const
 }
 
 auto ServerCapabilities::typeHierarchyProvider() const
-    -> std::optional<std::variant<std::monostate, bool, TypeHierarchyOptions,
+    -> std::optional<std::variant<bool, TypeHierarchyOptions,
                                   TypeHierarchyRegistrationOptions>> {
   if (!repr_->contains("typeHierarchyProvider")) return std::nullopt;
 
   auto& value = (*repr_)["typeHierarchyProvider"];
 
-  std::variant<std::monostate, bool, TypeHierarchyOptions,
-               TypeHierarchyRegistrationOptions>
+  std::variant<bool, TypeHierarchyOptions, TypeHierarchyRegistrationOptions>
       result;
 
   details::try_emplace(result, value);
@@ -13373,60 +13226,52 @@ auto ServerCapabilities::typeHierarchyProvider() const
   return result;
 }
 
-auto ServerCapabilities::inlineValueProvider() const
-    -> std::optional<std::variant<std::monostate, bool, InlineValueOptions,
-                                  InlineValueRegistrationOptions>> {
+auto ServerCapabilities::inlineValueProvider() const -> std::optional<
+    std::variant<bool, InlineValueOptions, InlineValueRegistrationOptions>> {
   if (!repr_->contains("inlineValueProvider")) return std::nullopt;
 
   auto& value = (*repr_)["inlineValueProvider"];
 
-  std::variant<std::monostate, bool, InlineValueOptions,
-               InlineValueRegistrationOptions>
-      result;
+  std::variant<bool, InlineValueOptions, InlineValueRegistrationOptions> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ServerCapabilities::inlayHintProvider() const
-    -> std::optional<std::variant<std::monostate, bool, InlayHintOptions,
-                                  InlayHintRegistrationOptions>> {
+auto ServerCapabilities::inlayHintProvider() const -> std::optional<
+    std::variant<bool, InlayHintOptions, InlayHintRegistrationOptions>> {
   if (!repr_->contains("inlayHintProvider")) return std::nullopt;
 
   auto& value = (*repr_)["inlayHintProvider"];
 
-  std::variant<std::monostate, bool, InlayHintOptions,
-               InlayHintRegistrationOptions>
-      result;
+  std::variant<bool, InlayHintOptions, InlayHintRegistrationOptions> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ServerCapabilities::diagnosticProvider() const
-    -> std::optional<std::variant<std::monostate, DiagnosticOptions,
-                                  DiagnosticRegistrationOptions>> {
+auto ServerCapabilities::diagnosticProvider() const -> std::optional<
+    std::variant<DiagnosticOptions, DiagnosticRegistrationOptions>> {
   if (!repr_->contains("diagnosticProvider")) return std::nullopt;
 
   auto& value = (*repr_)["diagnosticProvider"];
 
-  std::variant<std::monostate, DiagnosticOptions, DiagnosticRegistrationOptions>
-      result;
+  std::variant<DiagnosticOptions, DiagnosticRegistrationOptions> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ServerCapabilities::inlineCompletionProvider() const -> std::optional<
-    std::variant<std::monostate, bool, InlineCompletionOptions>> {
+auto ServerCapabilities::inlineCompletionProvider() const
+    -> std::optional<std::variant<bool, InlineCompletionOptions>> {
   if (!repr_->contains("inlineCompletionProvider")) return std::nullopt;
 
   auto& value = (*repr_)["inlineCompletionProvider"];
 
-  std::variant<std::monostate, bool, InlineCompletionOptions> result;
+  std::variant<bool, InlineCompletionOptions> result;
 
   details::try_emplace(result, value);
 
@@ -13462,29 +13307,22 @@ auto ServerCapabilities::positionEncoding(
 }
 
 auto ServerCapabilities::textDocumentSync(
-    std::optional<std::variant<std::monostate, TextDocumentSyncOptions,
-                               TextDocumentSyncKind>>
+    std::optional<std::variant<TextDocumentSyncOptions, TextDocumentSyncKind>>
         textDocumentSync) -> ServerCapabilities& {
   if (!textDocumentSync.has_value()) {
     repr_->erase("textDocumentSync");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(TextDocumentSyncOptions textDocumentSync) {
-      repr_->emplace("textDocumentSync", textDocumentSync);
+      (*repr_)["textDocumentSync"] = textDocumentSync;
     }
 
     void operator()(TextDocumentSyncKind textDocumentSync) {
-      repr_->emplace("textDocumentSync", static_cast<long>(textDocumentSync));
+      (*repr_)["textDocumentSync"] = static_cast<long>(textDocumentSync);
     }
   } v{repr_};
 
@@ -13494,7 +13332,7 @@ auto ServerCapabilities::textDocumentSync(
 }
 
 auto ServerCapabilities::notebookDocumentSync(
-    std::optional<std::variant<std::monostate, NotebookDocumentSyncOptions,
+    std::optional<std::variant<NotebookDocumentSyncOptions,
                                NotebookDocumentSyncRegistrationOptions>>
         notebookDocumentSync) -> ServerCapabilities& {
   if (!notebookDocumentSync.has_value()) {
@@ -13502,22 +13340,16 @@ auto ServerCapabilities::notebookDocumentSync(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(NotebookDocumentSyncOptions notebookDocumentSync) {
-      repr_->emplace("notebookDocumentSync", notebookDocumentSync);
+      (*repr_)["notebookDocumentSync"] = notebookDocumentSync;
     }
 
     void operator()(
         NotebookDocumentSyncRegistrationOptions notebookDocumentSync) {
-      repr_->emplace("notebookDocumentSync", notebookDocumentSync);
+      (*repr_)["notebookDocumentSync"] = notebookDocumentSync;
     }
   } v{repr_};
 
@@ -13533,33 +13365,27 @@ auto ServerCapabilities::completionProvider(
     repr_->erase("completionProvider");
     return *this;
   }
-  repr_->emplace("completionProvider", completionProvider.value());
+  (*repr_)["completionProvider"] = completionProvider.value();
   return *this;
 }
 
 auto ServerCapabilities::hoverProvider(
-    std::optional<std::variant<std::monostate, bool, HoverOptions>>
-        hoverProvider) -> ServerCapabilities& {
+    std::optional<std::variant<bool, HoverOptions>> hoverProvider)
+    -> ServerCapabilities& {
   if (!hoverProvider.has_value()) {
     repr_->erase("hoverProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool hoverProvider) {
-      repr_->emplace("hoverProvider", std::move(hoverProvider));
+      (*repr_)["hoverProvider"] = std::move(hoverProvider);
     }
 
     void operator()(HoverOptions hoverProvider) {
-      repr_->emplace("hoverProvider", hoverProvider);
+      (*repr_)["hoverProvider"] = hoverProvider;
     }
   } v{repr_};
 
@@ -13575,38 +13401,32 @@ auto ServerCapabilities::signatureHelpProvider(
     repr_->erase("signatureHelpProvider");
     return *this;
   }
-  repr_->emplace("signatureHelpProvider", signatureHelpProvider.value());
+  (*repr_)["signatureHelpProvider"] = signatureHelpProvider.value();
   return *this;
 }
 
 auto ServerCapabilities::declarationProvider(
-    std::optional<std::variant<std::monostate, bool, DeclarationOptions,
-                               DeclarationRegistrationOptions>>
+    std::optional<
+        std::variant<bool, DeclarationOptions, DeclarationRegistrationOptions>>
         declarationProvider) -> ServerCapabilities& {
   if (!declarationProvider.has_value()) {
     repr_->erase("declarationProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool declarationProvider) {
-      repr_->emplace("declarationProvider", std::move(declarationProvider));
+      (*repr_)["declarationProvider"] = std::move(declarationProvider);
     }
 
     void operator()(DeclarationOptions declarationProvider) {
-      repr_->emplace("declarationProvider", declarationProvider);
+      (*repr_)["declarationProvider"] = declarationProvider;
     }
 
     void operator()(DeclarationRegistrationOptions declarationProvider) {
-      repr_->emplace("declarationProvider", declarationProvider);
+      (*repr_)["declarationProvider"] = declarationProvider;
     }
   } v{repr_};
 
@@ -13616,28 +13436,22 @@ auto ServerCapabilities::declarationProvider(
 }
 
 auto ServerCapabilities::definitionProvider(
-    std::optional<std::variant<std::monostate, bool, DefinitionOptions>>
-        definitionProvider) -> ServerCapabilities& {
+    std::optional<std::variant<bool, DefinitionOptions>> definitionProvider)
+    -> ServerCapabilities& {
   if (!definitionProvider.has_value()) {
     repr_->erase("definitionProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool definitionProvider) {
-      repr_->emplace("definitionProvider", std::move(definitionProvider));
+      (*repr_)["definitionProvider"] = std::move(definitionProvider);
     }
 
     void operator()(DefinitionOptions definitionProvider) {
-      repr_->emplace("definitionProvider", definitionProvider);
+      (*repr_)["definitionProvider"] = definitionProvider;
     }
   } v{repr_};
 
@@ -13647,7 +13461,7 @@ auto ServerCapabilities::definitionProvider(
 }
 
 auto ServerCapabilities::typeDefinitionProvider(
-    std::optional<std::variant<std::monostate, bool, TypeDefinitionOptions,
+    std::optional<std::variant<bool, TypeDefinitionOptions,
                                TypeDefinitionRegistrationOptions>>
         typeDefinitionProvider) -> ServerCapabilities& {
   if (!typeDefinitionProvider.has_value()) {
@@ -13655,26 +13469,19 @@ auto ServerCapabilities::typeDefinitionProvider(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool typeDefinitionProvider) {
-      repr_->emplace("typeDefinitionProvider",
-                     std::move(typeDefinitionProvider));
+      (*repr_)["typeDefinitionProvider"] = std::move(typeDefinitionProvider);
     }
 
     void operator()(TypeDefinitionOptions typeDefinitionProvider) {
-      repr_->emplace("typeDefinitionProvider", typeDefinitionProvider);
+      (*repr_)["typeDefinitionProvider"] = typeDefinitionProvider;
     }
 
     void operator()(TypeDefinitionRegistrationOptions typeDefinitionProvider) {
-      repr_->emplace("typeDefinitionProvider", typeDefinitionProvider);
+      (*repr_)["typeDefinitionProvider"] = typeDefinitionProvider;
     }
   } v{repr_};
 
@@ -13684,7 +13491,7 @@ auto ServerCapabilities::typeDefinitionProvider(
 }
 
 auto ServerCapabilities::implementationProvider(
-    std::optional<std::variant<std::monostate, bool, ImplementationOptions,
+    std::optional<std::variant<bool, ImplementationOptions,
                                ImplementationRegistrationOptions>>
         implementationProvider) -> ServerCapabilities& {
   if (!implementationProvider.has_value()) {
@@ -13692,26 +13499,19 @@ auto ServerCapabilities::implementationProvider(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool implementationProvider) {
-      repr_->emplace("implementationProvider",
-                     std::move(implementationProvider));
+      (*repr_)["implementationProvider"] = std::move(implementationProvider);
     }
 
     void operator()(ImplementationOptions implementationProvider) {
-      repr_->emplace("implementationProvider", implementationProvider);
+      (*repr_)["implementationProvider"] = implementationProvider;
     }
 
     void operator()(ImplementationRegistrationOptions implementationProvider) {
-      repr_->emplace("implementationProvider", implementationProvider);
+      (*repr_)["implementationProvider"] = implementationProvider;
     }
   } v{repr_};
 
@@ -13721,28 +13521,22 @@ auto ServerCapabilities::implementationProvider(
 }
 
 auto ServerCapabilities::referencesProvider(
-    std::optional<std::variant<std::monostate, bool, ReferenceOptions>>
-        referencesProvider) -> ServerCapabilities& {
+    std::optional<std::variant<bool, ReferenceOptions>> referencesProvider)
+    -> ServerCapabilities& {
   if (!referencesProvider.has_value()) {
     repr_->erase("referencesProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool referencesProvider) {
-      repr_->emplace("referencesProvider", std::move(referencesProvider));
+      (*repr_)["referencesProvider"] = std::move(referencesProvider);
     }
 
     void operator()(ReferenceOptions referencesProvider) {
-      repr_->emplace("referencesProvider", referencesProvider);
+      (*repr_)["referencesProvider"] = referencesProvider;
     }
   } v{repr_};
 
@@ -13752,29 +13546,23 @@ auto ServerCapabilities::referencesProvider(
 }
 
 auto ServerCapabilities::documentHighlightProvider(
-    std::optional<std::variant<std::monostate, bool, DocumentHighlightOptions>>
+    std::optional<std::variant<bool, DocumentHighlightOptions>>
         documentHighlightProvider) -> ServerCapabilities& {
   if (!documentHighlightProvider.has_value()) {
     repr_->erase("documentHighlightProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool documentHighlightProvider) {
-      repr_->emplace("documentHighlightProvider",
-                     std::move(documentHighlightProvider));
+      (*repr_)["documentHighlightProvider"] =
+          std::move(documentHighlightProvider);
     }
 
     void operator()(DocumentHighlightOptions documentHighlightProvider) {
-      repr_->emplace("documentHighlightProvider", documentHighlightProvider);
+      (*repr_)["documentHighlightProvider"] = documentHighlightProvider;
     }
   } v{repr_};
 
@@ -13784,29 +13572,22 @@ auto ServerCapabilities::documentHighlightProvider(
 }
 
 auto ServerCapabilities::documentSymbolProvider(
-    std::optional<std::variant<std::monostate, bool, DocumentSymbolOptions>>
+    std::optional<std::variant<bool, DocumentSymbolOptions>>
         documentSymbolProvider) -> ServerCapabilities& {
   if (!documentSymbolProvider.has_value()) {
     repr_->erase("documentSymbolProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool documentSymbolProvider) {
-      repr_->emplace("documentSymbolProvider",
-                     std::move(documentSymbolProvider));
+      (*repr_)["documentSymbolProvider"] = std::move(documentSymbolProvider);
     }
 
     void operator()(DocumentSymbolOptions documentSymbolProvider) {
-      repr_->emplace("documentSymbolProvider", documentSymbolProvider);
+      (*repr_)["documentSymbolProvider"] = documentSymbolProvider;
     }
   } v{repr_};
 
@@ -13816,28 +13597,22 @@ auto ServerCapabilities::documentSymbolProvider(
 }
 
 auto ServerCapabilities::codeActionProvider(
-    std::optional<std::variant<std::monostate, bool, CodeActionOptions>>
-        codeActionProvider) -> ServerCapabilities& {
+    std::optional<std::variant<bool, CodeActionOptions>> codeActionProvider)
+    -> ServerCapabilities& {
   if (!codeActionProvider.has_value()) {
     repr_->erase("codeActionProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool codeActionProvider) {
-      repr_->emplace("codeActionProvider", std::move(codeActionProvider));
+      (*repr_)["codeActionProvider"] = std::move(codeActionProvider);
     }
 
     void operator()(CodeActionOptions codeActionProvider) {
-      repr_->emplace("codeActionProvider", codeActionProvider);
+      (*repr_)["codeActionProvider"] = codeActionProvider;
     }
   } v{repr_};
 
@@ -13852,7 +13627,7 @@ auto ServerCapabilities::codeLensProvider(
     repr_->erase("codeLensProvider");
     return *this;
   }
-  repr_->emplace("codeLensProvider", codeLensProvider.value());
+  (*repr_)["codeLensProvider"] = codeLensProvider.value();
   return *this;
 }
 
@@ -13863,12 +13638,12 @@ auto ServerCapabilities::documentLinkProvider(
     repr_->erase("documentLinkProvider");
     return *this;
   }
-  repr_->emplace("documentLinkProvider", documentLinkProvider.value());
+  (*repr_)["documentLinkProvider"] = documentLinkProvider.value();
   return *this;
 }
 
 auto ServerCapabilities::colorProvider(
-    std::optional<std::variant<std::monostate, bool, DocumentColorOptions,
+    std::optional<std::variant<bool, DocumentColorOptions,
                                DocumentColorRegistrationOptions>>
         colorProvider) -> ServerCapabilities& {
   if (!colorProvider.has_value()) {
@@ -13876,25 +13651,19 @@ auto ServerCapabilities::colorProvider(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool colorProvider) {
-      repr_->emplace("colorProvider", std::move(colorProvider));
+      (*repr_)["colorProvider"] = std::move(colorProvider);
     }
 
     void operator()(DocumentColorOptions colorProvider) {
-      repr_->emplace("colorProvider", colorProvider);
+      (*repr_)["colorProvider"] = colorProvider;
     }
 
     void operator()(DocumentColorRegistrationOptions colorProvider) {
-      repr_->emplace("colorProvider", colorProvider);
+      (*repr_)["colorProvider"] = colorProvider;
     }
   } v{repr_};
 
@@ -13904,29 +13673,22 @@ auto ServerCapabilities::colorProvider(
 }
 
 auto ServerCapabilities::workspaceSymbolProvider(
-    std::optional<std::variant<std::monostate, bool, WorkspaceSymbolOptions>>
+    std::optional<std::variant<bool, WorkspaceSymbolOptions>>
         workspaceSymbolProvider) -> ServerCapabilities& {
   if (!workspaceSymbolProvider.has_value()) {
     repr_->erase("workspaceSymbolProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool workspaceSymbolProvider) {
-      repr_->emplace("workspaceSymbolProvider",
-                     std::move(workspaceSymbolProvider));
+      (*repr_)["workspaceSymbolProvider"] = std::move(workspaceSymbolProvider);
     }
 
     void operator()(WorkspaceSymbolOptions workspaceSymbolProvider) {
-      repr_->emplace("workspaceSymbolProvider", workspaceSymbolProvider);
+      (*repr_)["workspaceSymbolProvider"] = workspaceSymbolProvider;
     }
   } v{repr_};
 
@@ -13936,29 +13698,23 @@ auto ServerCapabilities::workspaceSymbolProvider(
 }
 
 auto ServerCapabilities::documentFormattingProvider(
-    std::optional<std::variant<std::monostate, bool, DocumentFormattingOptions>>
+    std::optional<std::variant<bool, DocumentFormattingOptions>>
         documentFormattingProvider) -> ServerCapabilities& {
   if (!documentFormattingProvider.has_value()) {
     repr_->erase("documentFormattingProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool documentFormattingProvider) {
-      repr_->emplace("documentFormattingProvider",
-                     std::move(documentFormattingProvider));
+      (*repr_)["documentFormattingProvider"] =
+          std::move(documentFormattingProvider);
     }
 
     void operator()(DocumentFormattingOptions documentFormattingProvider) {
-      repr_->emplace("documentFormattingProvider", documentFormattingProvider);
+      (*repr_)["documentFormattingProvider"] = documentFormattingProvider;
     }
   } v{repr_};
 
@@ -13968,32 +13724,25 @@ auto ServerCapabilities::documentFormattingProvider(
 }
 
 auto ServerCapabilities::documentRangeFormattingProvider(
-    std::optional<
-        std::variant<std::monostate, bool, DocumentRangeFormattingOptions>>
+    std::optional<std::variant<bool, DocumentRangeFormattingOptions>>
         documentRangeFormattingProvider) -> ServerCapabilities& {
   if (!documentRangeFormattingProvider.has_value()) {
     repr_->erase("documentRangeFormattingProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool documentRangeFormattingProvider) {
-      repr_->emplace("documentRangeFormattingProvider",
-                     std::move(documentRangeFormattingProvider));
+      (*repr_)["documentRangeFormattingProvider"] =
+          std::move(documentRangeFormattingProvider);
     }
 
     void operator()(
         DocumentRangeFormattingOptions documentRangeFormattingProvider) {
-      repr_->emplace("documentRangeFormattingProvider",
-                     documentRangeFormattingProvider);
+      (*repr_)["documentRangeFormattingProvider"] =
+          documentRangeFormattingProvider;
     }
   } v{repr_};
 
@@ -14009,34 +13758,28 @@ auto ServerCapabilities::documentOnTypeFormattingProvider(
     repr_->erase("documentOnTypeFormattingProvider");
     return *this;
   }
-  repr_->emplace("documentOnTypeFormattingProvider",
-                 documentOnTypeFormattingProvider.value());
+  (*repr_)["documentOnTypeFormattingProvider"] =
+      documentOnTypeFormattingProvider.value();
   return *this;
 }
 
 auto ServerCapabilities::renameProvider(
-    std::optional<std::variant<std::monostate, bool, RenameOptions>>
-        renameProvider) -> ServerCapabilities& {
+    std::optional<std::variant<bool, RenameOptions>> renameProvider)
+    -> ServerCapabilities& {
   if (!renameProvider.has_value()) {
     repr_->erase("renameProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool renameProvider) {
-      repr_->emplace("renameProvider", std::move(renameProvider));
+      (*repr_)["renameProvider"] = std::move(renameProvider);
     }
 
     void operator()(RenameOptions renameProvider) {
-      repr_->emplace("renameProvider", renameProvider);
+      (*repr_)["renameProvider"] = renameProvider;
     }
   } v{repr_};
 
@@ -14046,7 +13789,7 @@ auto ServerCapabilities::renameProvider(
 }
 
 auto ServerCapabilities::foldingRangeProvider(
-    std::optional<std::variant<std::monostate, bool, FoldingRangeOptions,
+    std::optional<std::variant<bool, FoldingRangeOptions,
                                FoldingRangeRegistrationOptions>>
         foldingRangeProvider) -> ServerCapabilities& {
   if (!foldingRangeProvider.has_value()) {
@@ -14054,25 +13797,19 @@ auto ServerCapabilities::foldingRangeProvider(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool foldingRangeProvider) {
-      repr_->emplace("foldingRangeProvider", std::move(foldingRangeProvider));
+      (*repr_)["foldingRangeProvider"] = std::move(foldingRangeProvider);
     }
 
     void operator()(FoldingRangeOptions foldingRangeProvider) {
-      repr_->emplace("foldingRangeProvider", foldingRangeProvider);
+      (*repr_)["foldingRangeProvider"] = foldingRangeProvider;
     }
 
     void operator()(FoldingRangeRegistrationOptions foldingRangeProvider) {
-      repr_->emplace("foldingRangeProvider", foldingRangeProvider);
+      (*repr_)["foldingRangeProvider"] = foldingRangeProvider;
     }
   } v{repr_};
 
@@ -14082,7 +13819,7 @@ auto ServerCapabilities::foldingRangeProvider(
 }
 
 auto ServerCapabilities::selectionRangeProvider(
-    std::optional<std::variant<std::monostate, bool, SelectionRangeOptions,
+    std::optional<std::variant<bool, SelectionRangeOptions,
                                SelectionRangeRegistrationOptions>>
         selectionRangeProvider) -> ServerCapabilities& {
   if (!selectionRangeProvider.has_value()) {
@@ -14090,26 +13827,19 @@ auto ServerCapabilities::selectionRangeProvider(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool selectionRangeProvider) {
-      repr_->emplace("selectionRangeProvider",
-                     std::move(selectionRangeProvider));
+      (*repr_)["selectionRangeProvider"] = std::move(selectionRangeProvider);
     }
 
     void operator()(SelectionRangeOptions selectionRangeProvider) {
-      repr_->emplace("selectionRangeProvider", selectionRangeProvider);
+      (*repr_)["selectionRangeProvider"] = selectionRangeProvider;
     }
 
     void operator()(SelectionRangeRegistrationOptions selectionRangeProvider) {
-      repr_->emplace("selectionRangeProvider", selectionRangeProvider);
+      (*repr_)["selectionRangeProvider"] = selectionRangeProvider;
     }
   } v{repr_};
 
@@ -14125,12 +13855,12 @@ auto ServerCapabilities::executeCommandProvider(
     repr_->erase("executeCommandProvider");
     return *this;
   }
-  repr_->emplace("executeCommandProvider", executeCommandProvider.value());
+  (*repr_)["executeCommandProvider"] = executeCommandProvider.value();
   return *this;
 }
 
 auto ServerCapabilities::callHierarchyProvider(
-    std::optional<std::variant<std::monostate, bool, CallHierarchyOptions,
+    std::optional<std::variant<bool, CallHierarchyOptions,
                                CallHierarchyRegistrationOptions>>
         callHierarchyProvider) -> ServerCapabilities& {
   if (!callHierarchyProvider.has_value()) {
@@ -14138,25 +13868,19 @@ auto ServerCapabilities::callHierarchyProvider(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool callHierarchyProvider) {
-      repr_->emplace("callHierarchyProvider", std::move(callHierarchyProvider));
+      (*repr_)["callHierarchyProvider"] = std::move(callHierarchyProvider);
     }
 
     void operator()(CallHierarchyOptions callHierarchyProvider) {
-      repr_->emplace("callHierarchyProvider", callHierarchyProvider);
+      (*repr_)["callHierarchyProvider"] = callHierarchyProvider;
     }
 
     void operator()(CallHierarchyRegistrationOptions callHierarchyProvider) {
-      repr_->emplace("callHierarchyProvider", callHierarchyProvider);
+      (*repr_)["callHierarchyProvider"] = callHierarchyProvider;
     }
   } v{repr_};
 
@@ -14166,7 +13890,7 @@ auto ServerCapabilities::callHierarchyProvider(
 }
 
 auto ServerCapabilities::linkedEditingRangeProvider(
-    std::optional<std::variant<std::monostate, bool, LinkedEditingRangeOptions,
+    std::optional<std::variant<bool, LinkedEditingRangeOptions,
                                LinkedEditingRangeRegistrationOptions>>
         linkedEditingRangeProvider) -> ServerCapabilities& {
   if (!linkedEditingRangeProvider.has_value()) {
@@ -14174,27 +13898,21 @@ auto ServerCapabilities::linkedEditingRangeProvider(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool linkedEditingRangeProvider) {
-      repr_->emplace("linkedEditingRangeProvider",
-                     std::move(linkedEditingRangeProvider));
+      (*repr_)["linkedEditingRangeProvider"] =
+          std::move(linkedEditingRangeProvider);
     }
 
     void operator()(LinkedEditingRangeOptions linkedEditingRangeProvider) {
-      repr_->emplace("linkedEditingRangeProvider", linkedEditingRangeProvider);
+      (*repr_)["linkedEditingRangeProvider"] = linkedEditingRangeProvider;
     }
 
     void operator()(
         LinkedEditingRangeRegistrationOptions linkedEditingRangeProvider) {
-      repr_->emplace("linkedEditingRangeProvider", linkedEditingRangeProvider);
+      (*repr_)["linkedEditingRangeProvider"] = linkedEditingRangeProvider;
     }
   } v{repr_};
 
@@ -14204,29 +13922,23 @@ auto ServerCapabilities::linkedEditingRangeProvider(
 }
 
 auto ServerCapabilities::semanticTokensProvider(
-    std::optional<std::variant<std::monostate, SemanticTokensOptions,
-                               SemanticTokensRegistrationOptions>>
+    std::optional<
+        std::variant<SemanticTokensOptions, SemanticTokensRegistrationOptions>>
         semanticTokensProvider) -> ServerCapabilities& {
   if (!semanticTokensProvider.has_value()) {
     repr_->erase("semanticTokensProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(SemanticTokensOptions semanticTokensProvider) {
-      repr_->emplace("semanticTokensProvider", semanticTokensProvider);
+      (*repr_)["semanticTokensProvider"] = semanticTokensProvider;
     }
 
     void operator()(SemanticTokensRegistrationOptions semanticTokensProvider) {
-      repr_->emplace("semanticTokensProvider", semanticTokensProvider);
+      (*repr_)["semanticTokensProvider"] = semanticTokensProvider;
     }
   } v{repr_};
 
@@ -14236,33 +13948,27 @@ auto ServerCapabilities::semanticTokensProvider(
 }
 
 auto ServerCapabilities::monikerProvider(
-    std::optional<std::variant<std::monostate, bool, MonikerOptions,
-                               MonikerRegistrationOptions>>
+    std::optional<
+        std::variant<bool, MonikerOptions, MonikerRegistrationOptions>>
         monikerProvider) -> ServerCapabilities& {
   if (!monikerProvider.has_value()) {
     repr_->erase("monikerProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool monikerProvider) {
-      repr_->emplace("monikerProvider", std::move(monikerProvider));
+      (*repr_)["monikerProvider"] = std::move(monikerProvider);
     }
 
     void operator()(MonikerOptions monikerProvider) {
-      repr_->emplace("monikerProvider", monikerProvider);
+      (*repr_)["monikerProvider"] = monikerProvider;
     }
 
     void operator()(MonikerRegistrationOptions monikerProvider) {
-      repr_->emplace("monikerProvider", monikerProvider);
+      (*repr_)["monikerProvider"] = monikerProvider;
     }
   } v{repr_};
 
@@ -14272,7 +13978,7 @@ auto ServerCapabilities::monikerProvider(
 }
 
 auto ServerCapabilities::typeHierarchyProvider(
-    std::optional<std::variant<std::monostate, bool, TypeHierarchyOptions,
+    std::optional<std::variant<bool, TypeHierarchyOptions,
                                TypeHierarchyRegistrationOptions>>
         typeHierarchyProvider) -> ServerCapabilities& {
   if (!typeHierarchyProvider.has_value()) {
@@ -14280,25 +13986,19 @@ auto ServerCapabilities::typeHierarchyProvider(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool typeHierarchyProvider) {
-      repr_->emplace("typeHierarchyProvider", std::move(typeHierarchyProvider));
+      (*repr_)["typeHierarchyProvider"] = std::move(typeHierarchyProvider);
     }
 
     void operator()(TypeHierarchyOptions typeHierarchyProvider) {
-      repr_->emplace("typeHierarchyProvider", typeHierarchyProvider);
+      (*repr_)["typeHierarchyProvider"] = typeHierarchyProvider;
     }
 
     void operator()(TypeHierarchyRegistrationOptions typeHierarchyProvider) {
-      repr_->emplace("typeHierarchyProvider", typeHierarchyProvider);
+      (*repr_)["typeHierarchyProvider"] = typeHierarchyProvider;
     }
   } v{repr_};
 
@@ -14308,33 +14008,27 @@ auto ServerCapabilities::typeHierarchyProvider(
 }
 
 auto ServerCapabilities::inlineValueProvider(
-    std::optional<std::variant<std::monostate, bool, InlineValueOptions,
-                               InlineValueRegistrationOptions>>
+    std::optional<
+        std::variant<bool, InlineValueOptions, InlineValueRegistrationOptions>>
         inlineValueProvider) -> ServerCapabilities& {
   if (!inlineValueProvider.has_value()) {
     repr_->erase("inlineValueProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool inlineValueProvider) {
-      repr_->emplace("inlineValueProvider", std::move(inlineValueProvider));
+      (*repr_)["inlineValueProvider"] = std::move(inlineValueProvider);
     }
 
     void operator()(InlineValueOptions inlineValueProvider) {
-      repr_->emplace("inlineValueProvider", inlineValueProvider);
+      (*repr_)["inlineValueProvider"] = inlineValueProvider;
     }
 
     void operator()(InlineValueRegistrationOptions inlineValueProvider) {
-      repr_->emplace("inlineValueProvider", inlineValueProvider);
+      (*repr_)["inlineValueProvider"] = inlineValueProvider;
     }
   } v{repr_};
 
@@ -14344,33 +14038,27 @@ auto ServerCapabilities::inlineValueProvider(
 }
 
 auto ServerCapabilities::inlayHintProvider(
-    std::optional<std::variant<std::monostate, bool, InlayHintOptions,
-                               InlayHintRegistrationOptions>>
+    std::optional<
+        std::variant<bool, InlayHintOptions, InlayHintRegistrationOptions>>
         inlayHintProvider) -> ServerCapabilities& {
   if (!inlayHintProvider.has_value()) {
     repr_->erase("inlayHintProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool inlayHintProvider) {
-      repr_->emplace("inlayHintProvider", std::move(inlayHintProvider));
+      (*repr_)["inlayHintProvider"] = std::move(inlayHintProvider);
     }
 
     void operator()(InlayHintOptions inlayHintProvider) {
-      repr_->emplace("inlayHintProvider", inlayHintProvider);
+      (*repr_)["inlayHintProvider"] = inlayHintProvider;
     }
 
     void operator()(InlayHintRegistrationOptions inlayHintProvider) {
-      repr_->emplace("inlayHintProvider", inlayHintProvider);
+      (*repr_)["inlayHintProvider"] = inlayHintProvider;
     }
   } v{repr_};
 
@@ -14380,29 +14068,23 @@ auto ServerCapabilities::inlayHintProvider(
 }
 
 auto ServerCapabilities::diagnosticProvider(
-    std::optional<std::variant<std::monostate, DiagnosticOptions,
-                               DiagnosticRegistrationOptions>>
+    std::optional<
+        std::variant<DiagnosticOptions, DiagnosticRegistrationOptions>>
         diagnosticProvider) -> ServerCapabilities& {
   if (!diagnosticProvider.has_value()) {
     repr_->erase("diagnosticProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(DiagnosticOptions diagnosticProvider) {
-      repr_->emplace("diagnosticProvider", diagnosticProvider);
+      (*repr_)["diagnosticProvider"] = diagnosticProvider;
     }
 
     void operator()(DiagnosticRegistrationOptions diagnosticProvider) {
-      repr_->emplace("diagnosticProvider", diagnosticProvider);
+      (*repr_)["diagnosticProvider"] = diagnosticProvider;
     }
   } v{repr_};
 
@@ -14412,29 +14094,23 @@ auto ServerCapabilities::diagnosticProvider(
 }
 
 auto ServerCapabilities::inlineCompletionProvider(
-    std::optional<std::variant<std::monostate, bool, InlineCompletionOptions>>
+    std::optional<std::variant<bool, InlineCompletionOptions>>
         inlineCompletionProvider) -> ServerCapabilities& {
   if (!inlineCompletionProvider.has_value()) {
     repr_->erase("inlineCompletionProvider");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(bool inlineCompletionProvider) {
-      repr_->emplace("inlineCompletionProvider",
-                     std::move(inlineCompletionProvider));
+      (*repr_)["inlineCompletionProvider"] =
+          std::move(inlineCompletionProvider);
     }
 
     void operator()(InlineCompletionOptions inlineCompletionProvider) {
-      repr_->emplace("inlineCompletionProvider", inlineCompletionProvider);
+      (*repr_)["inlineCompletionProvider"] = inlineCompletionProvider;
     }
   } v{repr_};
 
@@ -14449,7 +14125,7 @@ auto ServerCapabilities::workspace(std::optional<WorkspaceOptions> workspace)
     repr_->erase("workspace");
     return *this;
   }
-  repr_->emplace("workspace", workspace.value());
+  (*repr_)["workspace"] = workspace.value();
   return *this;
 }
 
@@ -14472,6 +14148,7 @@ ServerInfo::operator bool() const {
 auto ServerInfo::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -14481,12 +14158,13 @@ auto ServerInfo::version() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto ServerInfo::name(std::string name) -> ServerInfo& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
@@ -14495,7 +14173,7 @@ auto ServerInfo::version(std::optional<std::string> version) -> ServerInfo& {
     repr_->erase("version");
     return *this;
   }
-  repr_->emplace("version", std::move(version.value()));
+  (*repr_)["version"] = std::move(version.value());
   return *this;
 }
 
@@ -14509,6 +14187,7 @@ VersionedTextDocumentIdentifier::operator bool() const {
 auto VersionedTextDocumentIdentifier::version() const -> int {
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<int>();
 }
@@ -14516,19 +14195,20 @@ auto VersionedTextDocumentIdentifier::version() const -> int {
 auto VersionedTextDocumentIdentifier::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto VersionedTextDocumentIdentifier::version(int version)
     -> VersionedTextDocumentIdentifier& {
-  repr_->emplace("version", std::move(version));
+  (*repr_)["version"] = std::move(version);
   return *this;
 }
 
 auto VersionedTextDocumentIdentifier::uri(std::string uri)
     -> VersionedTextDocumentIdentifier& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -14542,6 +14222,7 @@ auto SaveOptions::includeText() const -> std::optional<bool> {
 
   auto& value = (*repr_)["includeText"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -14551,7 +14232,7 @@ auto SaveOptions::includeText(std::optional<bool> includeText) -> SaveOptions& {
     repr_->erase("includeText");
     return *this;
   }
-  repr_->emplace("includeText", std::move(includeText.value()));
+  (*repr_)["includeText"] = std::move(includeText.value());
   return *this;
 }
 
@@ -14565,6 +14246,7 @@ FileEvent::operator bool() const {
 auto FileEvent::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -14576,12 +14258,12 @@ auto FileEvent::type() const -> FileChangeType {
 }
 
 auto FileEvent::uri(std::string uri) -> FileEvent& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto FileEvent::type(FileChangeType type) -> FileEvent& {
-  repr_->emplace("type", static_cast<long>(type));
+  (*repr_)["type"] = static_cast<long>(type);
   return *this;
 }
 
@@ -14621,7 +14303,7 @@ auto FileSystemWatcher::kind(std::optional<WatchKind> kind)
     repr_->erase("kind");
     return *this;
   }
-  repr_->emplace("kind", static_cast<long>(kind.value()));
+  (*repr_)["kind"] = static_cast<long>(kind.value());
   return *this;
 }
 
@@ -14646,13 +14328,12 @@ auto Diagnostic::severity() const -> std::optional<DiagnosticSeverity> {
   return DiagnosticSeverity(value);
 }
 
-auto Diagnostic::code() const
-    -> std::optional<std::variant<std::monostate, int, std::string>> {
+auto Diagnostic::code() const -> std::optional<std::variant<int, std::string>> {
   if (!repr_->contains("code")) return std::nullopt;
 
   auto& value = (*repr_)["code"];
 
-  std::variant<std::monostate, int, std::string> result;
+  std::variant<int, std::string> result;
 
   details::try_emplace(result, value);
 
@@ -14672,6 +14353,7 @@ auto Diagnostic::source() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["source"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -14679,6 +14361,7 @@ auto Diagnostic::source() const -> std::optional<std::string> {
 auto Diagnostic::message() const -> std::string {
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -14688,7 +14371,7 @@ auto Diagnostic::tags() const -> std::optional<Vector<DiagnosticTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<DiagnosticTag>(value);
 }
 
@@ -14698,7 +14381,7 @@ auto Diagnostic::relatedInformation() const
 
   auto& value = (*repr_)["relatedInformation"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<DiagnosticRelatedInformation>(value);
 }
 
@@ -14712,7 +14395,7 @@ auto Diagnostic::data() const -> std::optional<LSPAny> {
 }
 
 auto Diagnostic::range(Range range) -> Diagnostic& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -14722,32 +14405,23 @@ auto Diagnostic::severity(std::optional<DiagnosticSeverity> severity)
     repr_->erase("severity");
     return *this;
   }
-  repr_->emplace("severity", static_cast<long>(severity.value()));
+  (*repr_)["severity"] = static_cast<long>(severity.value());
   return *this;
 }
 
-auto Diagnostic::code(
-    std::optional<std::variant<std::monostate, int, std::string>> code)
+auto Diagnostic::code(std::optional<std::variant<int, std::string>> code)
     -> Diagnostic& {
   if (!code.has_value()) {
     repr_->erase("code");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(int code) { repr_->emplace("code", std::move(code)); }
+    void operator()(int code) { (*repr_)["code"] = std::move(code); }
 
-    void operator()(std::string code) {
-      repr_->emplace("code", std::move(code));
-    }
+    void operator()(std::string code) { (*repr_)["code"] = std::move(code); }
   } v{repr_};
 
   std::visit(v, code.value());
@@ -14761,7 +14435,7 @@ auto Diagnostic::codeDescription(std::optional<CodeDescription> codeDescription)
     repr_->erase("codeDescription");
     return *this;
   }
-  repr_->emplace("codeDescription", codeDescription.value());
+  (*repr_)["codeDescription"] = codeDescription.value();
   return *this;
 }
 
@@ -14770,12 +14444,12 @@ auto Diagnostic::source(std::optional<std::string> source) -> Diagnostic& {
     repr_->erase("source");
     return *this;
   }
-  repr_->emplace("source", std::move(source.value()));
+  (*repr_)["source"] = std::move(source.value());
   return *this;
 }
 
 auto Diagnostic::message(std::string message) -> Diagnostic& {
-  repr_->emplace("message", std::move(message));
+  (*repr_)["message"] = std::move(message);
   return *this;
 }
 
@@ -14826,13 +14500,14 @@ auto CompletionContext::triggerCharacter() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["triggerCharacter"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto CompletionContext::triggerKind(CompletionTriggerKind triggerKind)
     -> CompletionContext& {
-  repr_->emplace("triggerKind", static_cast<long>(triggerKind));
+  (*repr_)["triggerKind"] = static_cast<long>(triggerKind);
   return *this;
 }
 
@@ -14842,7 +14517,7 @@ auto CompletionContext::triggerCharacter(
     repr_->erase("triggerCharacter");
     return *this;
   }
-  repr_->emplace("triggerCharacter", std::move(triggerCharacter.value()));
+  (*repr_)["triggerCharacter"] = std::move(triggerCharacter.value());
   return *this;
 }
 
@@ -14856,6 +14531,7 @@ auto CompletionItemLabelDetails::detail() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["detail"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -14866,6 +14542,7 @@ auto CompletionItemLabelDetails::description() const
 
   auto& value = (*repr_)["description"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -14876,7 +14553,7 @@ auto CompletionItemLabelDetails::detail(std::optional<std::string> detail)
     repr_->erase("detail");
     return *this;
   }
-  repr_->emplace("detail", std::move(detail.value()));
+  (*repr_)["detail"] = std::move(detail.value());
   return *this;
 }
 
@@ -14886,7 +14563,7 @@ auto CompletionItemLabelDetails::description(
     repr_->erase("description");
     return *this;
   }
-  repr_->emplace("description", std::move(description.value()));
+  (*repr_)["description"] = std::move(description.value());
   return *this;
 }
 
@@ -14901,6 +14578,7 @@ InsertReplaceEdit::operator bool() const {
 auto InsertReplaceEdit::newText() const -> std::string {
   auto& value = (*repr_)["newText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -14918,17 +14596,17 @@ auto InsertReplaceEdit::replace() const -> Range {
 }
 
 auto InsertReplaceEdit::newText(std::string newText) -> InsertReplaceEdit& {
-  repr_->emplace("newText", std::move(newText));
+  (*repr_)["newText"] = std::move(newText);
   return *this;
 }
 
 auto InsertReplaceEdit::insert(Range insert) -> InsertReplaceEdit& {
-  repr_->emplace("insert", insert);
+  (*repr_)["insert"] = insert;
   return *this;
 }
 
 auto InsertReplaceEdit::replace(Range replace) -> InsertReplaceEdit& {
-  repr_->emplace("replace", replace);
+  (*repr_)["replace"] = replace;
   return *this;
 }
 
@@ -14943,17 +14621,17 @@ auto CompletionItemDefaults::commitCharacters() const
 
   auto& value = (*repr_)["commitCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
-auto CompletionItemDefaults::editRange() const -> std::optional<
-    std::variant<std::monostate, Range, EditRangeWithInsertReplace>> {
+auto CompletionItemDefaults::editRange() const
+    -> std::optional<std::variant<Range, EditRangeWithInsertReplace>> {
   if (!repr_->contains("editRange")) return std::nullopt;
 
   auto& value = (*repr_)["editRange"];
 
-  std::variant<std::monostate, Range, EditRangeWithInsertReplace> result;
+  std::variant<Range, EditRangeWithInsertReplace> result;
 
   details::try_emplace(result, value);
 
@@ -15000,27 +14678,20 @@ auto CompletionItemDefaults::commitCharacters(
 }
 
 auto CompletionItemDefaults::editRange(
-    std::optional<
-        std::variant<std::monostate, Range, EditRangeWithInsertReplace>>
-        editRange) -> CompletionItemDefaults& {
+    std::optional<std::variant<Range, EditRangeWithInsertReplace>> editRange)
+    -> CompletionItemDefaults& {
   if (!editRange.has_value()) {
     repr_->erase("editRange");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(Range editRange) { repr_->emplace("editRange", editRange); }
+    void operator()(Range editRange) { (*repr_)["editRange"] = editRange; }
 
     void operator()(EditRangeWithInsertReplace editRange) {
-      repr_->emplace("editRange", editRange);
+      (*repr_)["editRange"] = editRange;
     }
   } v{repr_};
 
@@ -15036,8 +14707,7 @@ auto CompletionItemDefaults::insertTextFormat(
     repr_->erase("insertTextFormat");
     return *this;
   }
-  repr_->emplace("insertTextFormat",
-                 static_cast<long>(insertTextFormat.value()));
+  (*repr_)["insertTextFormat"] = static_cast<long>(insertTextFormat.value());
   return *this;
 }
 
@@ -15047,7 +14717,7 @@ auto CompletionItemDefaults::insertTextMode(
     repr_->erase("insertTextMode");
     return *this;
   }
-  repr_->emplace("insertTextMode", static_cast<long>(insertTextMode.value()));
+  (*repr_)["insertTextMode"] = static_cast<long>(insertTextMode.value());
   return *this;
 }
 
@@ -15089,8 +14759,7 @@ auto CompletionItemApplyKinds::commitCharacters(
     repr_->erase("commitCharacters");
     return *this;
   }
-  repr_->emplace("commitCharacters",
-                 static_cast<long>(commitCharacters.value()));
+  (*repr_)["commitCharacters"] = static_cast<long>(commitCharacters.value());
   return *this;
 }
 
@@ -15100,7 +14769,7 @@ auto CompletionItemApplyKinds::data(std::optional<ApplyKind> data)
     repr_->erase("data");
     return *this;
   }
-  repr_->emplace("data", static_cast<long>(data.value()));
+  (*repr_)["data"] = static_cast<long>(data.value());
   return *this;
 }
 
@@ -15115,7 +14784,7 @@ auto CompletionOptions::triggerCharacters() const
 
   auto& value = (*repr_)["triggerCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -15125,7 +14794,7 @@ auto CompletionOptions::allCommitCharacters() const
 
   auto& value = (*repr_)["allCommitCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -15134,6 +14803,7 @@ auto CompletionOptions::resolveProvider() const -> std::optional<bool> {
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15152,6 +14822,7 @@ auto CompletionOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15185,7 +14856,7 @@ auto CompletionOptions::resolveProvider(std::optional<bool> resolveProvider)
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -15196,7 +14867,7 @@ auto CompletionOptions::completionItem(
     repr_->erase("completionItem");
     return *this;
   }
-  repr_->emplace("completionItem", completionItem.value());
+  (*repr_)["completionItem"] = completionItem.value();
   return *this;
 }
 
@@ -15206,7 +14877,7 @@ auto CompletionOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15220,6 +14891,7 @@ auto HoverOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15230,7 +14902,7 @@ auto HoverOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15253,6 +14925,7 @@ auto SignatureHelpContext::triggerCharacter() const
 
   auto& value = (*repr_)["triggerCharacter"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -15260,6 +14933,7 @@ auto SignatureHelpContext::triggerCharacter() const
 auto SignatureHelpContext::isRetrigger() const -> bool {
   auto& value = (*repr_)["isRetrigger"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15275,7 +14949,7 @@ auto SignatureHelpContext::activeSignatureHelp() const
 
 auto SignatureHelpContext::triggerKind(SignatureHelpTriggerKind triggerKind)
     -> SignatureHelpContext& {
-  repr_->emplace("triggerKind", static_cast<long>(triggerKind));
+  (*repr_)["triggerKind"] = static_cast<long>(triggerKind);
   return *this;
 }
 
@@ -15285,13 +14959,13 @@ auto SignatureHelpContext::triggerCharacter(
     repr_->erase("triggerCharacter");
     return *this;
   }
-  repr_->emplace("triggerCharacter", std::move(triggerCharacter.value()));
+  (*repr_)["triggerCharacter"] = std::move(triggerCharacter.value());
   return *this;
 }
 
 auto SignatureHelpContext::isRetrigger(bool isRetrigger)
     -> SignatureHelpContext& {
-  repr_->emplace("isRetrigger", std::move(isRetrigger));
+  (*repr_)["isRetrigger"] = std::move(isRetrigger);
   return *this;
 }
 
@@ -15301,7 +14975,7 @@ auto SignatureHelpContext::activeSignatureHelp(
     repr_->erase("activeSignatureHelp");
     return *this;
   }
-  repr_->emplace("activeSignatureHelp", activeSignatureHelp.value());
+  (*repr_)["activeSignatureHelp"] = activeSignatureHelp.value();
   return *this;
 }
 
@@ -15314,17 +14988,18 @@ SignatureInformation::operator bool() const {
 auto SignatureInformation::label() const -> std::string {
   auto& value = (*repr_)["label"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto SignatureInformation::documentation() const
-    -> std::optional<std::variant<std::monostate, std::string, MarkupContent>> {
+    -> std::optional<std::variant<std::string, MarkupContent>> {
   if (!repr_->contains("documentation")) return std::nullopt;
 
   auto& value = (*repr_)["documentation"];
 
-  std::variant<std::monostate, std::string, MarkupContent> result;
+  std::variant<std::string, MarkupContent> result;
 
   details::try_emplace(result, value);
 
@@ -15337,17 +15012,17 @@ auto SignatureInformation::parameters() const
 
   auto& value = (*repr_)["parameters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<ParameterInformation>(value);
 }
 
 auto SignatureInformation::activeParameter() const
-    -> std::optional<std::variant<std::monostate, long, std::nullptr_t>> {
+    -> std::optional<std::variant<long, std::nullptr_t>> {
   if (!repr_->contains("activeParameter")) return std::nullopt;
 
   auto& value = (*repr_)["activeParameter"];
 
-  std::variant<std::monostate, long, std::nullptr_t> result;
+  std::variant<long, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -15355,33 +15030,27 @@ auto SignatureInformation::activeParameter() const
 }
 
 auto SignatureInformation::label(std::string label) -> SignatureInformation& {
-  repr_->emplace("label", std::move(label));
+  (*repr_)["label"] = std::move(label);
   return *this;
 }
 
 auto SignatureInformation::documentation(
-    std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-        documentation) -> SignatureInformation& {
+    std::optional<std::variant<std::string, MarkupContent>> documentation)
+    -> SignatureInformation& {
   if (!documentation.has_value()) {
     repr_->erase("documentation");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string documentation) {
-      repr_->emplace("documentation", std::move(documentation));
+      (*repr_)["documentation"] = std::move(documentation);
     }
 
     void operator()(MarkupContent documentation) {
-      repr_->emplace("documentation", documentation);
+      (*repr_)["documentation"] = documentation;
     }
   } v{repr_};
 
@@ -15402,28 +15071,22 @@ auto SignatureInformation::parameters(
 }
 
 auto SignatureInformation::activeParameter(
-    std::optional<std::variant<std::monostate, long, std::nullptr_t>>
-        activeParameter) -> SignatureInformation& {
+    std::optional<std::variant<long, std::nullptr_t>> activeParameter)
+    -> SignatureInformation& {
   if (!activeParameter.has_value()) {
     repr_->erase("activeParameter");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(long activeParameter) {
-      repr_->emplace("activeParameter", std::move(activeParameter));
+      (*repr_)["activeParameter"] = std::move(activeParameter);
     }
 
     void operator()(std::nullptr_t activeParameter) {
-      repr_->emplace("activeParameter", std::move(activeParameter));
+      (*repr_)["activeParameter"] = std::move(activeParameter);
     }
   } v{repr_};
 
@@ -15443,7 +15106,7 @@ auto SignatureHelpOptions::triggerCharacters() const
 
   auto& value = (*repr_)["triggerCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -15453,7 +15116,7 @@ auto SignatureHelpOptions::retriggerCharacters() const
 
   auto& value = (*repr_)["retriggerCharacters"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -15462,6 +15125,7 @@ auto SignatureHelpOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15496,7 +15160,7 @@ auto SignatureHelpOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15510,6 +15174,7 @@ auto DefinitionOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15520,7 +15185,7 @@ auto DefinitionOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15533,13 +15198,14 @@ ReferenceContext::operator bool() const {
 auto ReferenceContext::includeDeclaration() const -> bool {
   auto& value = (*repr_)["includeDeclaration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto ReferenceContext::includeDeclaration(bool includeDeclaration)
     -> ReferenceContext& {
-  repr_->emplace("includeDeclaration", std::move(includeDeclaration));
+  (*repr_)["includeDeclaration"] = std::move(includeDeclaration);
   return *this;
 }
 
@@ -15553,6 +15219,7 @@ auto ReferenceOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15563,7 +15230,7 @@ auto ReferenceOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15577,6 +15244,7 @@ auto DocumentHighlightOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15587,7 +15255,7 @@ auto DocumentHighlightOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15601,6 +15269,7 @@ BaseSymbolInformation::operator bool() const {
 auto BaseSymbolInformation::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -15616,7 +15285,7 @@ auto BaseSymbolInformation::tags() const -> std::optional<Vector<SymbolTag>> {
 
   auto& value = (*repr_)["tags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SymbolTag>(value);
 }
 
@@ -15626,17 +15295,18 @@ auto BaseSymbolInformation::containerName() const
 
   auto& value = (*repr_)["containerName"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto BaseSymbolInformation::name(std::string name) -> BaseSymbolInformation& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
 auto BaseSymbolInformation::kind(SymbolKind kind) -> BaseSymbolInformation& {
-  repr_->emplace("kind", static_cast<long>(kind));
+  (*repr_)["kind"] = static_cast<long>(kind);
   return *this;
 }
 
@@ -15656,7 +15326,7 @@ auto BaseSymbolInformation::containerName(
     repr_->erase("containerName");
     return *this;
   }
-  repr_->emplace("containerName", std::move(containerName.value()));
+  (*repr_)["containerName"] = std::move(containerName.value());
   return *this;
 }
 
@@ -15670,6 +15340,7 @@ auto DocumentSymbolOptions::label() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["label"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -15679,6 +15350,7 @@ auto DocumentSymbolOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15689,7 +15361,7 @@ auto DocumentSymbolOptions::label(std::optional<std::string> label)
     repr_->erase("label");
     return *this;
   }
-  repr_->emplace("label", std::move(label.value()));
+  (*repr_)["label"] = std::move(label.value());
   return *this;
 }
 
@@ -15699,7 +15371,7 @@ auto DocumentSymbolOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15712,7 +15384,7 @@ CodeActionContext::operator bool() const {
 auto CodeActionContext::diagnostics() const -> Vector<Diagnostic> {
   auto& value = (*repr_)["diagnostics"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Diagnostic>(value);
 }
 
@@ -15721,7 +15393,7 @@ auto CodeActionContext::only() const -> std::optional<Vector<CodeActionKind>> {
 
   auto& value = (*repr_)["only"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CodeActionKind>(value);
 }
 
@@ -15756,7 +15428,7 @@ auto CodeActionContext::triggerKind(
     repr_->erase("triggerKind");
     return *this;
   }
-  repr_->emplace("triggerKind", static_cast<long>(triggerKind.value()));
+  (*repr_)["triggerKind"] = static_cast<long>(triggerKind.value());
   return *this;
 }
 
@@ -15769,12 +15441,13 @@ CodeActionDisabled::operator bool() const {
 auto CodeActionDisabled::reason() const -> std::string {
   auto& value = (*repr_)["reason"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto CodeActionDisabled::reason(std::string reason) -> CodeActionDisabled& {
-  repr_->emplace("reason", std::move(reason));
+  (*repr_)["reason"] = std::move(reason);
   return *this;
 }
 
@@ -15789,7 +15462,7 @@ auto CodeActionOptions::codeActionKinds() const
 
   auto& value = (*repr_)["codeActionKinds"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CodeActionKind>(value);
 }
 
@@ -15799,7 +15472,7 @@ auto CodeActionOptions::documentation() const
 
   auto& value = (*repr_)["documentation"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CodeActionKindDocumentation>(value);
 }
 
@@ -15808,6 +15481,7 @@ auto CodeActionOptions::resolveProvider() const -> std::optional<bool> {
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15817,6 +15491,7 @@ auto CodeActionOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15849,7 +15524,7 @@ auto CodeActionOptions::resolveProvider(std::optional<bool> resolveProvider)
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -15859,7 +15534,7 @@ auto CodeActionOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15872,12 +15547,13 @@ LocationUriOnly::operator bool() const {
 auto LocationUriOnly::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto LocationUriOnly::uri(std::string uri) -> LocationUriOnly& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -15891,6 +15567,7 @@ auto WorkspaceSymbolOptions::resolveProvider() const -> std::optional<bool> {
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15900,6 +15577,7 @@ auto WorkspaceSymbolOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15910,7 +15588,7 @@ auto WorkspaceSymbolOptions::resolveProvider(
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -15920,7 +15598,7 @@ auto WorkspaceSymbolOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15934,6 +15612,7 @@ auto CodeLensOptions::resolveProvider() const -> std::optional<bool> {
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15943,6 +15622,7 @@ auto CodeLensOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15953,7 +15633,7 @@ auto CodeLensOptions::resolveProvider(std::optional<bool> resolveProvider)
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -15963,7 +15643,7 @@ auto CodeLensOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -15977,6 +15657,7 @@ auto DocumentLinkOptions::resolveProvider() const -> std::optional<bool> {
 
   auto& value = (*repr_)["resolveProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15986,6 +15667,7 @@ auto DocumentLinkOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -15996,7 +15678,7 @@ auto DocumentLinkOptions::resolveProvider(std::optional<bool> resolveProvider)
     repr_->erase("resolveProvider");
     return *this;
   }
-  repr_->emplace("resolveProvider", std::move(resolveProvider.value()));
+  (*repr_)["resolveProvider"] = std::move(resolveProvider.value());
   return *this;
 }
 
@@ -16006,7 +15688,7 @@ auto DocumentLinkOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -16020,6 +15702,7 @@ FormattingOptions::operator bool() const {
 auto FormattingOptions::tabSize() const -> long {
   auto& value = (*repr_)["tabSize"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -16027,6 +15710,7 @@ auto FormattingOptions::tabSize() const -> long {
 auto FormattingOptions::insertSpaces() const -> bool {
   auto& value = (*repr_)["insertSpaces"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16036,6 +15720,7 @@ auto FormattingOptions::trimTrailingWhitespace() const -> std::optional<bool> {
 
   auto& value = (*repr_)["trimTrailingWhitespace"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16045,6 +15730,7 @@ auto FormattingOptions::insertFinalNewline() const -> std::optional<bool> {
 
   auto& value = (*repr_)["insertFinalNewline"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16054,17 +15740,18 @@ auto FormattingOptions::trimFinalNewlines() const -> std::optional<bool> {
 
   auto& value = (*repr_)["trimFinalNewlines"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto FormattingOptions::tabSize(long tabSize) -> FormattingOptions& {
-  repr_->emplace("tabSize", std::move(tabSize));
+  (*repr_)["tabSize"] = std::move(tabSize);
   return *this;
 }
 
 auto FormattingOptions::insertSpaces(bool insertSpaces) -> FormattingOptions& {
-  repr_->emplace("insertSpaces", std::move(insertSpaces));
+  (*repr_)["insertSpaces"] = std::move(insertSpaces);
   return *this;
 }
 
@@ -16074,8 +15761,8 @@ auto FormattingOptions::trimTrailingWhitespace(
     repr_->erase("trimTrailingWhitespace");
     return *this;
   }
-  repr_->emplace("trimTrailingWhitespace",
-                 std::move(trimTrailingWhitespace.value()));
+  (*repr_)["trimTrailingWhitespace"] =
+      std::move(trimTrailingWhitespace.value());
   return *this;
 }
 
@@ -16085,7 +15772,7 @@ auto FormattingOptions::insertFinalNewline(
     repr_->erase("insertFinalNewline");
     return *this;
   }
-  repr_->emplace("insertFinalNewline", std::move(insertFinalNewline.value()));
+  (*repr_)["insertFinalNewline"] = std::move(insertFinalNewline.value());
   return *this;
 }
 
@@ -16095,7 +15782,7 @@ auto FormattingOptions::trimFinalNewlines(std::optional<bool> trimFinalNewlines)
     repr_->erase("trimFinalNewlines");
     return *this;
   }
-  repr_->emplace("trimFinalNewlines", std::move(trimFinalNewlines.value()));
+  (*repr_)["trimFinalNewlines"] = std::move(trimFinalNewlines.value());
   return *this;
 }
 
@@ -16110,6 +15797,7 @@ auto DocumentFormattingOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16120,7 +15808,7 @@ auto DocumentFormattingOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -16135,6 +15823,7 @@ auto DocumentRangeFormattingOptions::rangesSupport() const
 
   auto& value = (*repr_)["rangesSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16145,6 +15834,7 @@ auto DocumentRangeFormattingOptions::workDoneProgress() const
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16155,7 +15845,7 @@ auto DocumentRangeFormattingOptions::rangesSupport(
     repr_->erase("rangesSupport");
     return *this;
   }
-  repr_->emplace("rangesSupport", std::move(rangesSupport.value()));
+  (*repr_)["rangesSupport"] = std::move(rangesSupport.value());
   return *this;
 }
 
@@ -16165,7 +15855,7 @@ auto DocumentRangeFormattingOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -16179,6 +15869,7 @@ auto DocumentOnTypeFormattingOptions::firstTriggerCharacter() const
     -> std::string {
   auto& value = (*repr_)["firstTriggerCharacter"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -16189,13 +15880,13 @@ auto DocumentOnTypeFormattingOptions::moreTriggerCharacter() const
 
   auto& value = (*repr_)["moreTriggerCharacter"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
 auto DocumentOnTypeFormattingOptions::firstTriggerCharacter(
     std::string firstTriggerCharacter) -> DocumentOnTypeFormattingOptions& {
-  repr_->emplace("firstTriggerCharacter", std::move(firstTriggerCharacter));
+  (*repr_)["firstTriggerCharacter"] = std::move(firstTriggerCharacter);
   return *this;
 }
 
@@ -16222,6 +15913,7 @@ auto RenameOptions::prepareProvider() const -> std::optional<bool> {
 
   auto& value = (*repr_)["prepareProvider"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16231,6 +15923,7 @@ auto RenameOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16241,7 +15934,7 @@ auto RenameOptions::prepareProvider(std::optional<bool> prepareProvider)
     repr_->erase("prepareProvider");
     return *this;
   }
-  repr_->emplace("prepareProvider", std::move(prepareProvider.value()));
+  (*repr_)["prepareProvider"] = std::move(prepareProvider.value());
   return *this;
 }
 
@@ -16251,7 +15944,7 @@ auto RenameOptions::workDoneProgress(std::optional<bool> workDoneProgress)
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -16271,18 +15964,19 @@ auto PrepareRenamePlaceholder::range() const -> Range {
 auto PrepareRenamePlaceholder::placeholder() const -> std::string {
   auto& value = (*repr_)["placeholder"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto PrepareRenamePlaceholder::range(Range range) -> PrepareRenamePlaceholder& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto PrepareRenamePlaceholder::placeholder(std::string placeholder)
     -> PrepareRenamePlaceholder& {
-  repr_->emplace("placeholder", std::move(placeholder));
+  (*repr_)["placeholder"] = std::move(placeholder);
   return *this;
 }
 
@@ -16295,13 +15989,14 @@ PrepareRenameDefaultBehavior::operator bool() const {
 auto PrepareRenameDefaultBehavior::defaultBehavior() const -> bool {
   auto& value = (*repr_)["defaultBehavior"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto PrepareRenameDefaultBehavior::defaultBehavior(bool defaultBehavior)
     -> PrepareRenameDefaultBehavior& {
-  repr_->emplace("defaultBehavior", std::move(defaultBehavior));
+  (*repr_)["defaultBehavior"] = std::move(defaultBehavior);
   return *this;
 }
 
@@ -16314,7 +16009,7 @@ ExecuteCommandOptions::operator bool() const {
 auto ExecuteCommandOptions::commands() const -> Vector<std::string> {
   auto& value = (*repr_)["commands"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -16323,6 +16018,7 @@ auto ExecuteCommandOptions::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16339,7 +16035,7 @@ auto ExecuteCommandOptions::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -16353,6 +16049,7 @@ auto WorkspaceEditMetadata::isRefactoring() const -> std::optional<bool> {
 
   auto& value = (*repr_)["isRefactoring"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16363,7 +16060,7 @@ auto WorkspaceEditMetadata::isRefactoring(std::optional<bool> isRefactoring)
     repr_->erase("isRefactoring");
     return *this;
   }
-  repr_->emplace("isRefactoring", std::move(isRefactoring.value()));
+  (*repr_)["isRefactoring"] = std::move(isRefactoring.value());
   return *this;
 }
 
@@ -16377,14 +16074,14 @@ SemanticTokensLegend::operator bool() const {
 auto SemanticTokensLegend::tokenTypes() const -> Vector<std::string> {
   auto& value = (*repr_)["tokenTypes"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
 auto SemanticTokensLegend::tokenModifiers() const -> Vector<std::string> {
   auto& value = (*repr_)["tokenModifiers"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -16410,6 +16107,7 @@ auto SemanticTokensFullDelta::delta() const -> std::optional<bool> {
 
   auto& value = (*repr_)["delta"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16420,7 +16118,7 @@ auto SemanticTokensFullDelta::delta(std::optional<bool> delta)
     repr_->erase("delta");
     return *this;
   }
-  repr_->emplace("delta", std::move(delta.value()));
+  (*repr_)["delta"] = std::move(delta.value());
   return *this;
 }
 
@@ -16432,10 +16130,10 @@ OptionalVersionedTextDocumentIdentifier::operator bool() const {
 }
 
 auto OptionalVersionedTextDocumentIdentifier::version() const
-    -> std::variant<std::monostate, int, std::nullptr_t> {
+    -> std::variant<int, std::nullptr_t> {
   auto& value = (*repr_)["version"];
 
-  std::variant<std::monostate, int, std::nullptr_t> result;
+  std::variant<int, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -16445,28 +16143,21 @@ auto OptionalVersionedTextDocumentIdentifier::version() const
 auto OptionalVersionedTextDocumentIdentifier::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto OptionalVersionedTextDocumentIdentifier::version(
-    std::variant<std::monostate, int, std::nullptr_t> version)
+    std::variant<int, std::nullptr_t> version)
     -> OptionalVersionedTextDocumentIdentifier& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(int version) {
-      repr_->emplace("version", std::move(version));
-    }
+    void operator()(int version) { (*repr_)["version"] = std::move(version); }
 
     void operator()(std::nullptr_t version) {
-      repr_->emplace("version", std::move(version));
+      (*repr_)["version"] = std::move(version);
     }
   } v{repr_};
 
@@ -16477,7 +16168,7 @@ auto OptionalVersionedTextDocumentIdentifier::version(
 
 auto OptionalVersionedTextDocumentIdentifier::uri(std::string uri)
     -> OptionalVersionedTextDocumentIdentifier& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
@@ -16492,6 +16183,7 @@ AnnotatedTextEdit::operator bool() const {
 auto AnnotatedTextEdit::annotationId() const -> ChangeAnnotationIdentifier {
   auto& value = (*repr_)["annotationId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -16505,6 +16197,7 @@ auto AnnotatedTextEdit::range() const -> Range {
 auto AnnotatedTextEdit::newText() const -> std::string {
   auto& value = (*repr_)["newText"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -16516,12 +16209,12 @@ auto AnnotatedTextEdit::annotationId(ChangeAnnotationIdentifier annotationId)
 }
 
 auto AnnotatedTextEdit::range(Range range) -> AnnotatedTextEdit& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto AnnotatedTextEdit::newText(std::string newText) -> AnnotatedTextEdit& {
-  repr_->emplace("newText", std::move(newText));
+  (*repr_)["newText"] = std::move(newText);
   return *this;
 }
 
@@ -16550,17 +16243,18 @@ auto SnippetTextEdit::annotationId() const
 
   auto& value = (*repr_)["annotationId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto SnippetTextEdit::range(Range range) -> SnippetTextEdit& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto SnippetTextEdit::snippet(StringValue snippet) -> SnippetTextEdit& {
-  repr_->emplace("snippet", snippet);
+  (*repr_)["snippet"] = snippet;
   return *this;
 }
 
@@ -16584,6 +16278,7 @@ ResourceOperation::operator bool() const {
 auto ResourceOperation::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -16594,12 +16289,13 @@ auto ResourceOperation::annotationId() const
 
   auto& value = (*repr_)["annotationId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto ResourceOperation::kind(std::string kind) -> ResourceOperation& {
-  repr_->emplace("kind", std::move(kind));
+  (*repr_)["kind"] = std::move(kind);
   return *this;
 }
 
@@ -16624,6 +16320,7 @@ auto CreateFileOptions::overwrite() const -> std::optional<bool> {
 
   auto& value = (*repr_)["overwrite"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16633,6 +16330,7 @@ auto CreateFileOptions::ignoreIfExists() const -> std::optional<bool> {
 
   auto& value = (*repr_)["ignoreIfExists"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16643,7 +16341,7 @@ auto CreateFileOptions::overwrite(std::optional<bool> overwrite)
     repr_->erase("overwrite");
     return *this;
   }
-  repr_->emplace("overwrite", std::move(overwrite.value()));
+  (*repr_)["overwrite"] = std::move(overwrite.value());
   return *this;
 }
 
@@ -16653,7 +16351,7 @@ auto CreateFileOptions::ignoreIfExists(std::optional<bool> ignoreIfExists)
     repr_->erase("ignoreIfExists");
     return *this;
   }
-  repr_->emplace("ignoreIfExists", std::move(ignoreIfExists.value()));
+  (*repr_)["ignoreIfExists"] = std::move(ignoreIfExists.value());
   return *this;
 }
 
@@ -16667,6 +16365,7 @@ auto RenameFileOptions::overwrite() const -> std::optional<bool> {
 
   auto& value = (*repr_)["overwrite"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16676,6 +16375,7 @@ auto RenameFileOptions::ignoreIfExists() const -> std::optional<bool> {
 
   auto& value = (*repr_)["ignoreIfExists"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16686,7 +16386,7 @@ auto RenameFileOptions::overwrite(std::optional<bool> overwrite)
     repr_->erase("overwrite");
     return *this;
   }
-  repr_->emplace("overwrite", std::move(overwrite.value()));
+  (*repr_)["overwrite"] = std::move(overwrite.value());
   return *this;
 }
 
@@ -16696,7 +16396,7 @@ auto RenameFileOptions::ignoreIfExists(std::optional<bool> ignoreIfExists)
     repr_->erase("ignoreIfExists");
     return *this;
   }
-  repr_->emplace("ignoreIfExists", std::move(ignoreIfExists.value()));
+  (*repr_)["ignoreIfExists"] = std::move(ignoreIfExists.value());
   return *this;
 }
 
@@ -16710,6 +16410,7 @@ auto DeleteFileOptions::recursive() const -> std::optional<bool> {
 
   auto& value = (*repr_)["recursive"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16719,6 +16420,7 @@ auto DeleteFileOptions::ignoreIfNotExists() const -> std::optional<bool> {
 
   auto& value = (*repr_)["ignoreIfNotExists"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -16729,7 +16431,7 @@ auto DeleteFileOptions::recursive(std::optional<bool> recursive)
     repr_->erase("recursive");
     return *this;
   }
-  repr_->emplace("recursive", std::move(recursive.value()));
+  (*repr_)["recursive"] = std::move(recursive.value());
   return *this;
 }
 
@@ -16739,7 +16441,7 @@ auto DeleteFileOptions::ignoreIfNotExists(std::optional<bool> ignoreIfNotExists)
     repr_->erase("ignoreIfNotExists");
     return *this;
   }
-  repr_->emplace("ignoreIfNotExists", std::move(ignoreIfNotExists.value()));
+  (*repr_)["ignoreIfNotExists"] = std::move(ignoreIfNotExists.value());
   return *this;
 }
 
@@ -16752,6 +16454,7 @@ FileOperationPattern::operator bool() const {
 auto FileOperationPattern::glob() const -> std::string {
   auto& value = (*repr_)["glob"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -16775,7 +16478,7 @@ auto FileOperationPattern::options() const
 }
 
 auto FileOperationPattern::glob(std::string glob) -> FileOperationPattern& {
-  repr_->emplace("glob", std::move(glob));
+  (*repr_)["glob"] = std::move(glob);
   return *this;
 }
 
@@ -16796,7 +16499,7 @@ auto FileOperationPattern::options(
     repr_->erase("options");
     return *this;
   }
-  repr_->emplace("options", options.value());
+  (*repr_)["options"] = options.value();
   return *this;
 }
 
@@ -16813,15 +16516,16 @@ WorkspaceFullDocumentDiagnosticReport::operator bool() const {
 auto WorkspaceFullDocumentDiagnosticReport::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto WorkspaceFullDocumentDiagnosticReport::version() const
-    -> std::variant<std::monostate, int, std::nullptr_t> {
+    -> std::variant<int, std::nullptr_t> {
   auto& value = (*repr_)["version"];
 
-  std::variant<std::monostate, int, std::nullptr_t> result;
+  std::variant<int, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -16831,6 +16535,7 @@ auto WorkspaceFullDocumentDiagnosticReport::version() const
 auto WorkspaceFullDocumentDiagnosticReport::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "full";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -16841,6 +16546,7 @@ auto WorkspaceFullDocumentDiagnosticReport::resultId() const
 
   auto& value = (*repr_)["resultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -16849,34 +16555,26 @@ auto WorkspaceFullDocumentDiagnosticReport::items() const
     -> Vector<Diagnostic> {
   auto& value = (*repr_)["items"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<Diagnostic>(value);
 }
 
 auto WorkspaceFullDocumentDiagnosticReport::uri(std::string uri)
     -> WorkspaceFullDocumentDiagnosticReport& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto WorkspaceFullDocumentDiagnosticReport::version(
-    std::variant<std::monostate, int, std::nullptr_t> version)
+    std::variant<int, std::nullptr_t> version)
     -> WorkspaceFullDocumentDiagnosticReport& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(int version) {
-      repr_->emplace("version", std::move(version));
-    }
+    void operator()(int version) { (*repr_)["version"] = std::move(version); }
 
     void operator()(std::nullptr_t version) {
-      repr_->emplace("version", std::move(version));
+      (*repr_)["version"] = std::move(version);
     }
   } v{repr_};
 
@@ -16899,7 +16597,7 @@ auto WorkspaceFullDocumentDiagnosticReport::resultId(
     repr_->erase("resultId");
     return *this;
   }
-  repr_->emplace("resultId", std::move(resultId.value()));
+  (*repr_)["resultId"] = std::move(resultId.value());
   return *this;
 }
 
@@ -16923,15 +16621,16 @@ WorkspaceUnchangedDocumentDiagnosticReport::operator bool() const {
 auto WorkspaceUnchangedDocumentDiagnosticReport::uri() const -> std::string {
   auto& value = (*repr_)["uri"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto WorkspaceUnchangedDocumentDiagnosticReport::version() const
-    -> std::variant<std::monostate, int, std::nullptr_t> {
+    -> std::variant<int, std::nullptr_t> {
   auto& value = (*repr_)["version"];
 
-  std::variant<std::monostate, int, std::nullptr_t> result;
+  std::variant<int, std::nullptr_t> result;
 
   details::try_emplace(result, value);
 
@@ -16941,6 +16640,7 @@ auto WorkspaceUnchangedDocumentDiagnosticReport::version() const
 auto WorkspaceUnchangedDocumentDiagnosticReport::kind() const -> std::string {
   auto& value = (*repr_)["kind"];
 
+  if (value.is_null()) value = "unchanged";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -16949,34 +16649,27 @@ auto WorkspaceUnchangedDocumentDiagnosticReport::resultId() const
     -> std::string {
   auto& value = (*repr_)["resultId"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto WorkspaceUnchangedDocumentDiagnosticReport::uri(std::string uri)
     -> WorkspaceUnchangedDocumentDiagnosticReport& {
-  repr_->emplace("uri", std::move(uri));
+  (*repr_)["uri"] = std::move(uri);
   return *this;
 }
 
 auto WorkspaceUnchangedDocumentDiagnosticReport::version(
-    std::variant<std::monostate, int, std::nullptr_t> version)
+    std::variant<int, std::nullptr_t> version)
     -> WorkspaceUnchangedDocumentDiagnosticReport& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(int version) {
-      repr_->emplace("version", std::move(version));
-    }
+    void operator()(int version) { (*repr_)["version"] = std::move(version); }
 
     void operator()(std::nullptr_t version) {
-      repr_->emplace("version", std::move(version));
+      (*repr_)["version"] = std::move(version);
     }
   } v{repr_};
 
@@ -16994,7 +16687,7 @@ auto WorkspaceUnchangedDocumentDiagnosticReport::kind(std::string kind)
 
 auto WorkspaceUnchangedDocumentDiagnosticReport::resultId(std::string resultId)
     -> WorkspaceUnchangedDocumentDiagnosticReport& {
-  repr_->emplace("resultId", std::move(resultId));
+  (*repr_)["resultId"] = std::move(resultId);
   return *this;
 }
 
@@ -17014,6 +16707,7 @@ auto NotebookCell::kind() const -> NotebookCellKind {
 auto NotebookCell::document() const -> std::string {
   auto& value = (*repr_)["document"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -17036,12 +16730,12 @@ auto NotebookCell::executionSummary() const -> std::optional<ExecutionSummary> {
 }
 
 auto NotebookCell::kind(NotebookCellKind kind) -> NotebookCell& {
-  repr_->emplace("kind", static_cast<long>(kind));
+  (*repr_)["kind"] = static_cast<long>(kind);
   return *this;
 }
 
 auto NotebookCell::document(std::string document) -> NotebookCell& {
-  repr_->emplace("document", std::move(document));
+  (*repr_)["document"] = std::move(document);
   return *this;
 }
 
@@ -17061,7 +16755,7 @@ auto NotebookCell::executionSummary(
     repr_->erase("executionSummary");
     return *this;
   }
-  repr_->emplace("executionSummary", executionSummary.value());
+  (*repr_)["executionSummary"] = executionSummary.value();
   return *this;
 }
 
@@ -17072,10 +16766,10 @@ NotebookDocumentFilterWithNotebook::operator bool() const {
 }
 
 auto NotebookDocumentFilterWithNotebook::notebook() const
-    -> std::variant<std::monostate, std::string, NotebookDocumentFilter> {
+    -> std::variant<std::string, NotebookDocumentFilter> {
   auto& value = (*repr_)["notebook"];
 
-  std::variant<std::monostate, std::string, NotebookDocumentFilter> result;
+  std::variant<std::string, NotebookDocumentFilter> result;
 
   details::try_emplace(result, value);
 
@@ -17088,24 +16782,18 @@ auto NotebookDocumentFilterWithNotebook::cells() const
 
   auto& value = (*repr_)["cells"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<NotebookCellLanguage>(value);
 }
 
 auto NotebookDocumentFilterWithNotebook::notebook(
-    std::variant<std::monostate, std::string, NotebookDocumentFilter> notebook)
+    std::variant<std::string, NotebookDocumentFilter> notebook)
     -> NotebookDocumentFilterWithNotebook& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string notebook) {
-      repr_->emplace("notebook", std::move(notebook));
+      (*repr_)["notebook"] = std::move(notebook);
     }
 
     void operator()(NotebookDocumentFilter notebook) {
@@ -17137,13 +16825,13 @@ NotebookDocumentFilterWithCells::operator bool() const {
   return true;
 }
 
-auto NotebookDocumentFilterWithCells::notebook() const -> std::optional<
-    std::variant<std::monostate, std::string, NotebookDocumentFilter>> {
+auto NotebookDocumentFilterWithCells::notebook() const
+    -> std::optional<std::variant<std::string, NotebookDocumentFilter>> {
   if (!repr_->contains("notebook")) return std::nullopt;
 
   auto& value = (*repr_)["notebook"];
 
-  std::variant<std::monostate, std::string, NotebookDocumentFilter> result;
+  std::variant<std::string, NotebookDocumentFilter> result;
 
   details::try_emplace(result, value);
 
@@ -17154,30 +16842,23 @@ auto NotebookDocumentFilterWithCells::cells() const
     -> Vector<NotebookCellLanguage> {
   auto& value = (*repr_)["cells"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<NotebookCellLanguage>(value);
 }
 
 auto NotebookDocumentFilterWithCells::notebook(
-    std::optional<
-        std::variant<std::monostate, std::string, NotebookDocumentFilter>>
-        notebook) -> NotebookDocumentFilterWithCells& {
+    std::optional<std::variant<std::string, NotebookDocumentFilter>> notebook)
+    -> NotebookDocumentFilterWithCells& {
   if (!notebook.has_value()) {
     repr_->erase("notebook");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string notebook) {
-      repr_->emplace("notebook", std::move(notebook));
+      (*repr_)["notebook"] = std::move(notebook);
     }
 
     void operator()(NotebookDocumentFilter notebook) {
@@ -17218,7 +16899,7 @@ auto NotebookDocumentCellChanges::data() const
 
   auto& value = (*repr_)["data"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<NotebookCell>(value);
 }
 
@@ -17228,7 +16909,7 @@ auto NotebookDocumentCellChanges::textContent() const
 
   auto& value = (*repr_)["textContent"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<NotebookDocumentCellContentChanges>(value);
 }
 
@@ -17239,7 +16920,7 @@ auto NotebookDocumentCellChanges::structure(
     repr_->erase("structure");
     return *this;
   }
-  repr_->emplace("structure", structure.value());
+  (*repr_)["structure"] = structure.value();
   return *this;
 }
 
@@ -17281,17 +16962,18 @@ auto SelectedCompletionInfo::range() const -> Range {
 auto SelectedCompletionInfo::text() const -> std::string {
   auto& value = (*repr_)["text"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto SelectedCompletionInfo::range(Range range) -> SelectedCompletionInfo& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
 auto SelectedCompletionInfo::text(std::string text) -> SelectedCompletionInfo& {
-  repr_->emplace("text", std::move(text));
+  (*repr_)["text"] = std::move(text);
   return *this;
 }
 
@@ -17304,6 +16986,7 @@ ClientInfo::operator bool() const {
 auto ClientInfo::name() const -> std::string {
   auto& value = (*repr_)["name"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -17313,12 +16996,13 @@ auto ClientInfo::version() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto ClientInfo::name(std::string name) -> ClientInfo& {
-  repr_->emplace("name", std::move(name));
+  (*repr_)["name"] = std::move(name);
   return *this;
 }
 
@@ -17327,7 +17011,7 @@ auto ClientInfo::version(std::optional<std::string> version) -> ClientInfo& {
     repr_->erase("version");
     return *this;
   }
-  repr_->emplace("version", std::move(version.value()));
+  (*repr_)["version"] = std::move(version.value());
   return *this;
 }
 
@@ -17397,7 +17081,7 @@ auto ClientCapabilities::workspace(
     repr_->erase("workspace");
     return *this;
   }
-  repr_->emplace("workspace", workspace.value());
+  (*repr_)["workspace"] = workspace.value();
   return *this;
 }
 
@@ -17408,7 +17092,7 @@ auto ClientCapabilities::textDocument(
     repr_->erase("textDocument");
     return *this;
   }
-  repr_->emplace("textDocument", textDocument.value());
+  (*repr_)["textDocument"] = textDocument.value();
   return *this;
 }
 
@@ -17419,7 +17103,7 @@ auto ClientCapabilities::notebookDocument(
     repr_->erase("notebookDocument");
     return *this;
   }
-  repr_->emplace("notebookDocument", notebookDocument.value());
+  (*repr_)["notebookDocument"] = notebookDocument.value();
   return *this;
 }
 
@@ -17429,7 +17113,7 @@ auto ClientCapabilities::window(std::optional<WindowClientCapabilities> window)
     repr_->erase("window");
     return *this;
   }
-  repr_->emplace("window", window.value());
+  (*repr_)["window"] = window.value();
   return *this;
 }
 
@@ -17439,7 +17123,7 @@ auto ClientCapabilities::general(
     repr_->erase("general");
     return *this;
   }
-  repr_->emplace("general", general.value());
+  (*repr_)["general"] = general.value();
   return *this;
 }
 
@@ -17463,6 +17147,7 @@ auto TextDocumentSyncOptions::openClose() const -> std::optional<bool> {
 
   auto& value = (*repr_)["openClose"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -17481,6 +17166,7 @@ auto TextDocumentSyncOptions::willSave() const -> std::optional<bool> {
 
   auto& value = (*repr_)["willSave"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -17490,17 +17176,18 @@ auto TextDocumentSyncOptions::willSaveWaitUntil() const -> std::optional<bool> {
 
   auto& value = (*repr_)["willSaveWaitUntil"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto TextDocumentSyncOptions::save() const
-    -> std::optional<std::variant<std::monostate, bool, SaveOptions>> {
+    -> std::optional<std::variant<bool, SaveOptions>> {
   if (!repr_->contains("save")) return std::nullopt;
 
   auto& value = (*repr_)["save"];
 
-  std::variant<std::monostate, bool, SaveOptions> result;
+  std::variant<bool, SaveOptions> result;
 
   details::try_emplace(result, value);
 
@@ -17513,7 +17200,7 @@ auto TextDocumentSyncOptions::openClose(std::optional<bool> openClose)
     repr_->erase("openClose");
     return *this;
   }
-  repr_->emplace("openClose", std::move(openClose.value()));
+  (*repr_)["openClose"] = std::move(openClose.value());
   return *this;
 }
 
@@ -17523,7 +17210,7 @@ auto TextDocumentSyncOptions::change(std::optional<TextDocumentSyncKind> change)
     repr_->erase("change");
     return *this;
   }
-  repr_->emplace("change", static_cast<long>(change.value()));
+  (*repr_)["change"] = static_cast<long>(change.value());
   return *this;
 }
 
@@ -17533,7 +17220,7 @@ auto TextDocumentSyncOptions::willSave(std::optional<bool> willSave)
     repr_->erase("willSave");
     return *this;
   }
-  repr_->emplace("willSave", std::move(willSave.value()));
+  (*repr_)["willSave"] = std::move(willSave.value());
   return *this;
 }
 
@@ -17543,30 +17230,24 @@ auto TextDocumentSyncOptions::willSaveWaitUntil(
     repr_->erase("willSaveWaitUntil");
     return *this;
   }
-  repr_->emplace("willSaveWaitUntil", std::move(willSaveWaitUntil.value()));
+  (*repr_)["willSaveWaitUntil"] = std::move(willSaveWaitUntil.value());
   return *this;
 }
 
 auto TextDocumentSyncOptions::save(
-    std::optional<std::variant<std::monostate, bool, SaveOptions>> save)
+    std::optional<std::variant<bool, SaveOptions>> save)
     -> TextDocumentSyncOptions& {
   if (!save.has_value()) {
     repr_->erase("save");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(bool save) { repr_->emplace("save", std::move(save)); }
+    void operator()(bool save) { (*repr_)["save"] = std::move(save); }
 
-    void operator()(SaveOptions save) { repr_->emplace("save", save); }
+    void operator()(SaveOptions save) { (*repr_)["save"] = save; }
   } v{repr_};
 
   std::visit(v, save.value());
@@ -17598,13 +17279,13 @@ auto WorkspaceOptions::fileOperations() const
 }
 
 auto WorkspaceOptions::textDocumentContent() const
-    -> std::optional<std::variant<std::monostate, TextDocumentContentOptions,
+    -> std::optional<std::variant<TextDocumentContentOptions,
                                   TextDocumentContentRegistrationOptions>> {
   if (!repr_->contains("textDocumentContent")) return std::nullopt;
 
   auto& value = (*repr_)["textDocumentContent"];
 
-  std::variant<std::monostate, TextDocumentContentOptions,
+  std::variant<TextDocumentContentOptions,
                TextDocumentContentRegistrationOptions>
       result;
 
@@ -17620,7 +17301,7 @@ auto WorkspaceOptions::workspaceFolders(
     repr_->erase("workspaceFolders");
     return *this;
   }
-  repr_->emplace("workspaceFolders", workspaceFolders.value());
+  (*repr_)["workspaceFolders"] = workspaceFolders.value();
   return *this;
 }
 
@@ -17630,12 +17311,12 @@ auto WorkspaceOptions::fileOperations(
     repr_->erase("fileOperations");
     return *this;
   }
-  repr_->emplace("fileOperations", fileOperations.value());
+  (*repr_)["fileOperations"] = fileOperations.value();
   return *this;
 }
 
 auto WorkspaceOptions::textDocumentContent(
-    std::optional<std::variant<std::monostate, TextDocumentContentOptions,
+    std::optional<std::variant<TextDocumentContentOptions,
                                TextDocumentContentRegistrationOptions>>
         textDocumentContent) -> WorkspaceOptions& {
   if (!textDocumentContent.has_value()) {
@@ -17643,22 +17324,16 @@ auto WorkspaceOptions::textDocumentContent(
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(TextDocumentContentOptions textDocumentContent) {
-      repr_->emplace("textDocumentContent", textDocumentContent);
+      (*repr_)["textDocumentContent"] = textDocumentContent;
     }
 
     void operator()(
         TextDocumentContentRegistrationOptions textDocumentContent) {
-      repr_->emplace("textDocumentContent", textDocumentContent);
+      (*repr_)["textDocumentContent"] = textDocumentContent;
     }
   } v{repr_};
 
@@ -17686,6 +17361,7 @@ auto TextDocumentContentChangePartial::rangeLength() const
 
   auto& value = (*repr_)["rangeLength"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -17693,13 +17369,14 @@ auto TextDocumentContentChangePartial::rangeLength() const
 auto TextDocumentContentChangePartial::text() const -> std::string {
   auto& value = (*repr_)["text"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TextDocumentContentChangePartial::range(Range range)
     -> TextDocumentContentChangePartial& {
-  repr_->emplace("range", range);
+  (*repr_)["range"] = range;
   return *this;
 }
 
@@ -17709,13 +17386,13 @@ auto TextDocumentContentChangePartial::rangeLength(
     repr_->erase("rangeLength");
     return *this;
   }
-  repr_->emplace("rangeLength", std::move(rangeLength.value()));
+  (*repr_)["rangeLength"] = std::move(rangeLength.value());
   return *this;
 }
 
 auto TextDocumentContentChangePartial::text(std::string text)
     -> TextDocumentContentChangePartial& {
-  repr_->emplace("text", std::move(text));
+  (*repr_)["text"] = std::move(text);
   return *this;
 }
 
@@ -17728,13 +17405,14 @@ TextDocumentContentChangeWholeDocument::operator bool() const {
 auto TextDocumentContentChangeWholeDocument::text() const -> std::string {
   auto& value = (*repr_)["text"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto TextDocumentContentChangeWholeDocument::text(std::string text)
     -> TextDocumentContentChangeWholeDocument& {
-  repr_->emplace("text", std::move(text));
+  (*repr_)["text"] = std::move(text);
   return *this;
 }
 
@@ -17747,12 +17425,13 @@ CodeDescription::operator bool() const {
 auto CodeDescription::href() const -> std::string {
   auto& value = (*repr_)["href"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto CodeDescription::href(std::string href) -> CodeDescription& {
-  repr_->emplace("href", std::move(href));
+  (*repr_)["href"] = std::move(href);
   return *this;
 }
 
@@ -17772,19 +17451,20 @@ auto DiagnosticRelatedInformation::location() const -> Location {
 auto DiagnosticRelatedInformation::message() const -> std::string {
   auto& value = (*repr_)["message"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto DiagnosticRelatedInformation::location(Location location)
     -> DiagnosticRelatedInformation& {
-  repr_->emplace("location", location);
+  (*repr_)["location"] = location;
   return *this;
 }
 
 auto DiagnosticRelatedInformation::message(std::string message)
     -> DiagnosticRelatedInformation& {
-  repr_->emplace("message", std::move(message));
+  (*repr_)["message"] = std::move(message);
   return *this;
 }
 
@@ -17809,13 +17489,13 @@ auto EditRangeWithInsertReplace::replace() const -> Range {
 
 auto EditRangeWithInsertReplace::insert(Range insert)
     -> EditRangeWithInsertReplace& {
-  repr_->emplace("insert", insert);
+  (*repr_)["insert"] = insert;
   return *this;
 }
 
 auto EditRangeWithInsertReplace::replace(Range replace)
     -> EditRangeWithInsertReplace& {
-  repr_->emplace("replace", replace);
+  (*repr_)["replace"] = replace;
   return *this;
 }
 
@@ -17830,6 +17510,7 @@ auto ServerCompletionItemOptions::labelDetailsSupport() const
 
   auto& value = (*repr_)["labelDetailsSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -17840,7 +17521,7 @@ auto ServerCompletionItemOptions::labelDetailsSupport(
     repr_->erase("labelDetailsSupport");
     return *this;
   }
-  repr_->emplace("labelDetailsSupport", std::move(labelDetailsSupport.value()));
+  (*repr_)["labelDetailsSupport"] = std::move(labelDetailsSupport.value());
   return *this;
 }
 
@@ -17854,6 +17535,7 @@ MarkedStringWithLanguage::operator bool() const {
 auto MarkedStringWithLanguage::language() const -> std::string {
   auto& value = (*repr_)["language"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -17861,19 +17543,20 @@ auto MarkedStringWithLanguage::language() const -> std::string {
 auto MarkedStringWithLanguage::value() const -> std::string {
   auto& value = (*repr_)["value"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto MarkedStringWithLanguage::language(std::string language)
     -> MarkedStringWithLanguage& {
-  repr_->emplace("language", std::move(language));
+  (*repr_)["language"] = std::move(language);
   return *this;
 }
 
 auto MarkedStringWithLanguage::value(std::string value)
     -> MarkedStringWithLanguage& {
-  repr_->emplace("value", std::move(value));
+  (*repr_)["value"] = std::move(value);
   return *this;
 }
 
@@ -17884,10 +17567,10 @@ ParameterInformation::operator bool() const {
 }
 
 auto ParameterInformation::label() const
-    -> std::variant<std::monostate, std::string, std::tuple<long, long>> {
+    -> std::variant<std::string, std::tuple<long, long>> {
   auto& value = (*repr_)["label"];
 
-  std::variant<std::monostate, std::string, std::tuple<long, long>> result;
+  std::variant<std::string, std::tuple<long, long>> result;
 
   details::try_emplace(result, value);
 
@@ -17895,12 +17578,12 @@ auto ParameterInformation::label() const
 }
 
 auto ParameterInformation::documentation() const
-    -> std::optional<std::variant<std::monostate, std::string, MarkupContent>> {
+    -> std::optional<std::variant<std::string, MarkupContent>> {
   if (!repr_->contains("documentation")) return std::nullopt;
 
   auto& value = (*repr_)["documentation"];
 
-  std::variant<std::monostate, std::string, MarkupContent> result;
+  std::variant<std::string, MarkupContent> result;
 
   details::try_emplace(result, value);
 
@@ -17908,20 +17591,12 @@ auto ParameterInformation::documentation() const
 }
 
 auto ParameterInformation::label(
-    std::variant<std::monostate, std::string, std::tuple<long, long>> label)
+    std::variant<std::string, std::tuple<long, long>> label)
     -> ParameterInformation& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(std::string label) {
-      repr_->emplace("label", std::move(label));
-    }
+    void operator()(std::string label) { (*repr_)["label"] = std::move(label); }
 
     void operator()(std::tuple<long, long> label) {
       lsp_runtime_error("ParameterInformation::label: not implement yet");
@@ -17934,28 +17609,22 @@ auto ParameterInformation::label(
 }
 
 auto ParameterInformation::documentation(
-    std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-        documentation) -> ParameterInformation& {
+    std::optional<std::variant<std::string, MarkupContent>> documentation)
+    -> ParameterInformation& {
   if (!documentation.has_value()) {
     repr_->erase("documentation");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string documentation) {
-      repr_->emplace("documentation", std::move(documentation));
+      (*repr_)["documentation"] = std::move(documentation);
     }
 
     void operator()(MarkupContent documentation) {
-      repr_->emplace("documentation", documentation);
+      (*repr_)["documentation"] = documentation;
     }
   } v{repr_};
 
@@ -17991,7 +17660,7 @@ auto CodeActionKindDocumentation::kind(CodeActionKind kind)
 
 auto CodeActionKindDocumentation::command(Command command)
     -> CodeActionKindDocumentation& {
-  repr_->emplace("command", command);
+  (*repr_)["command"] = command;
   return *this;
 }
 
@@ -18002,10 +17671,10 @@ NotebookCellTextDocumentFilter::operator bool() const {
 }
 
 auto NotebookCellTextDocumentFilter::notebook() const
-    -> std::variant<std::monostate, std::string, NotebookDocumentFilter> {
+    -> std::variant<std::string, NotebookDocumentFilter> {
   auto& value = (*repr_)["notebook"];
 
-  std::variant<std::monostate, std::string, NotebookDocumentFilter> result;
+  std::variant<std::string, NotebookDocumentFilter> result;
 
   details::try_emplace(result, value);
 
@@ -18018,24 +17687,19 @@ auto NotebookCellTextDocumentFilter::language() const
 
   auto& value = (*repr_)["language"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto NotebookCellTextDocumentFilter::notebook(
-    std::variant<std::monostate, std::string, NotebookDocumentFilter> notebook)
+    std::variant<std::string, NotebookDocumentFilter> notebook)
     -> NotebookCellTextDocumentFilter& {
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string notebook) {
-      repr_->emplace("notebook", std::move(notebook));
+      (*repr_)["notebook"] = std::move(notebook);
     }
 
     void operator()(NotebookDocumentFilter notebook) {
@@ -18055,7 +17719,7 @@ auto NotebookCellTextDocumentFilter::language(
     repr_->erase("language");
     return *this;
   }
-  repr_->emplace("language", std::move(language.value()));
+  (*repr_)["language"] = std::move(language.value());
   return *this;
 }
 
@@ -18069,6 +17733,7 @@ auto FileOperationPatternOptions::ignoreCase() const -> std::optional<bool> {
 
   auto& value = (*repr_)["ignoreCase"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -18079,7 +17744,7 @@ auto FileOperationPatternOptions::ignoreCase(std::optional<bool> ignoreCase)
     repr_->erase("ignoreCase");
     return *this;
   }
-  repr_->emplace("ignoreCase", std::move(ignoreCase.value()));
+  (*repr_)["ignoreCase"] = std::move(ignoreCase.value());
   return *this;
 }
 
@@ -18092,6 +17757,7 @@ ExecutionSummary::operator bool() const {
 auto ExecutionSummary::executionOrder() const -> long {
   auto& value = (*repr_)["executionOrder"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -18101,13 +17767,14 @@ auto ExecutionSummary::success() const -> std::optional<bool> {
 
   auto& value = (*repr_)["success"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto ExecutionSummary::executionOrder(long executionOrder)
     -> ExecutionSummary& {
-  repr_->emplace("executionOrder", std::move(executionOrder));
+  (*repr_)["executionOrder"] = std::move(executionOrder);
   return *this;
 }
 
@@ -18117,7 +17784,7 @@ auto ExecutionSummary::success(std::optional<bool> success)
     repr_->erase("success");
     return *this;
   }
-  repr_->emplace("success", std::move(success.value()));
+  (*repr_)["success"] = std::move(success.value());
   return *this;
 }
 
@@ -18130,13 +17797,14 @@ NotebookCellLanguage::operator bool() const {
 auto NotebookCellLanguage::language() const -> std::string {
   auto& value = (*repr_)["language"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto NotebookCellLanguage::language(std::string language)
     -> NotebookCellLanguage& {
-  repr_->emplace("language", std::move(language));
+  (*repr_)["language"] = std::move(language);
   return *this;
 }
 
@@ -18159,7 +17827,7 @@ auto NotebookDocumentCellChangeStructure::didOpen() const
 
   auto& value = (*repr_)["didOpen"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextDocumentItem>(value);
 }
 
@@ -18169,13 +17837,13 @@ auto NotebookDocumentCellChangeStructure::didClose() const
 
   auto& value = (*repr_)["didClose"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextDocumentIdentifier>(value);
 }
 
 auto NotebookDocumentCellChangeStructure::array(NotebookCellArrayChange array)
     -> NotebookDocumentCellChangeStructure& {
-  repr_->emplace("array", array);
+  (*repr_)["array"] = array;
   return *this;
 }
 
@@ -18221,14 +17889,14 @@ auto NotebookDocumentCellContentChanges::changes() const
     -> Vector<TextDocumentContentChangeEvent> {
   auto& value = (*repr_)["changes"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TextDocumentContentChangeEvent>(value);
 }
 
 auto NotebookDocumentCellContentChanges::document(
     VersionedTextDocumentIdentifier document)
     -> NotebookDocumentCellContentChanges& {
-  repr_->emplace("document", document);
+  (*repr_)["document"] = document;
   return *this;
 }
 
@@ -18250,6 +17918,7 @@ auto WorkspaceClientCapabilities::applyEdit() const -> std::optional<bool> {
 
   auto& value = (*repr_)["applyEdit"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -18305,6 +17974,7 @@ auto WorkspaceClientCapabilities::workspaceFolders() const
 
   auto& value = (*repr_)["workspaceFolders"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -18314,6 +17984,7 @@ auto WorkspaceClientCapabilities::configuration() const -> std::optional<bool> {
 
   auto& value = (*repr_)["configuration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -18396,7 +18067,7 @@ auto WorkspaceClientCapabilities::applyEdit(std::optional<bool> applyEdit)
     repr_->erase("applyEdit");
     return *this;
   }
-  repr_->emplace("applyEdit", std::move(applyEdit.value()));
+  (*repr_)["applyEdit"] = std::move(applyEdit.value());
   return *this;
 }
 
@@ -18407,7 +18078,7 @@ auto WorkspaceClientCapabilities::workspaceEdit(
     repr_->erase("workspaceEdit");
     return *this;
   }
-  repr_->emplace("workspaceEdit", workspaceEdit.value());
+  (*repr_)["workspaceEdit"] = workspaceEdit.value();
   return *this;
 }
 
@@ -18418,7 +18089,7 @@ auto WorkspaceClientCapabilities::didChangeConfiguration(
     repr_->erase("didChangeConfiguration");
     return *this;
   }
-  repr_->emplace("didChangeConfiguration", didChangeConfiguration.value());
+  (*repr_)["didChangeConfiguration"] = didChangeConfiguration.value();
   return *this;
 }
 
@@ -18429,7 +18100,7 @@ auto WorkspaceClientCapabilities::didChangeWatchedFiles(
     repr_->erase("didChangeWatchedFiles");
     return *this;
   }
-  repr_->emplace("didChangeWatchedFiles", didChangeWatchedFiles.value());
+  (*repr_)["didChangeWatchedFiles"] = didChangeWatchedFiles.value();
   return *this;
 }
 
@@ -18440,7 +18111,7 @@ auto WorkspaceClientCapabilities::symbol(
     repr_->erase("symbol");
     return *this;
   }
-  repr_->emplace("symbol", symbol.value());
+  (*repr_)["symbol"] = symbol.value();
   return *this;
 }
 
@@ -18451,7 +18122,7 @@ auto WorkspaceClientCapabilities::executeCommand(
     repr_->erase("executeCommand");
     return *this;
   }
-  repr_->emplace("executeCommand", executeCommand.value());
+  (*repr_)["executeCommand"] = executeCommand.value();
   return *this;
 }
 
@@ -18461,7 +18132,7 @@ auto WorkspaceClientCapabilities::workspaceFolders(
     repr_->erase("workspaceFolders");
     return *this;
   }
-  repr_->emplace("workspaceFolders", std::move(workspaceFolders.value()));
+  (*repr_)["workspaceFolders"] = std::move(workspaceFolders.value());
   return *this;
 }
 
@@ -18471,7 +18142,7 @@ auto WorkspaceClientCapabilities::configuration(
     repr_->erase("configuration");
     return *this;
   }
-  repr_->emplace("configuration", std::move(configuration.value()));
+  (*repr_)["configuration"] = std::move(configuration.value());
   return *this;
 }
 
@@ -18482,7 +18153,7 @@ auto WorkspaceClientCapabilities::semanticTokens(
     repr_->erase("semanticTokens");
     return *this;
   }
-  repr_->emplace("semanticTokens", semanticTokens.value());
+  (*repr_)["semanticTokens"] = semanticTokens.value();
   return *this;
 }
 
@@ -18493,7 +18164,7 @@ auto WorkspaceClientCapabilities::codeLens(
     repr_->erase("codeLens");
     return *this;
   }
-  repr_->emplace("codeLens", codeLens.value());
+  (*repr_)["codeLens"] = codeLens.value();
   return *this;
 }
 
@@ -18504,7 +18175,7 @@ auto WorkspaceClientCapabilities::fileOperations(
     repr_->erase("fileOperations");
     return *this;
   }
-  repr_->emplace("fileOperations", fileOperations.value());
+  (*repr_)["fileOperations"] = fileOperations.value();
   return *this;
 }
 
@@ -18515,7 +18186,7 @@ auto WorkspaceClientCapabilities::inlineValue(
     repr_->erase("inlineValue");
     return *this;
   }
-  repr_->emplace("inlineValue", inlineValue.value());
+  (*repr_)["inlineValue"] = inlineValue.value();
   return *this;
 }
 
@@ -18526,7 +18197,7 @@ auto WorkspaceClientCapabilities::inlayHint(
     repr_->erase("inlayHint");
     return *this;
   }
-  repr_->emplace("inlayHint", inlayHint.value());
+  (*repr_)["inlayHint"] = inlayHint.value();
   return *this;
 }
 
@@ -18537,7 +18208,7 @@ auto WorkspaceClientCapabilities::diagnostics(
     repr_->erase("diagnostics");
     return *this;
   }
-  repr_->emplace("diagnostics", diagnostics.value());
+  (*repr_)["diagnostics"] = diagnostics.value();
   return *this;
 }
 
@@ -18548,7 +18219,7 @@ auto WorkspaceClientCapabilities::foldingRange(
     repr_->erase("foldingRange");
     return *this;
   }
-  repr_->emplace("foldingRange", foldingRange.value());
+  (*repr_)["foldingRange"] = foldingRange.value();
   return *this;
 }
 
@@ -18559,7 +18230,7 @@ auto WorkspaceClientCapabilities::textDocumentContent(
     repr_->erase("textDocumentContent");
     return *this;
   }
-  repr_->emplace("textDocumentContent", textDocumentContent.value());
+  (*repr_)["textDocumentContent"] = textDocumentContent.value();
   return *this;
 }
 
@@ -18863,7 +18534,7 @@ auto TextDocumentClientCapabilities::synchronization(
     repr_->erase("synchronization");
     return *this;
   }
-  repr_->emplace("synchronization", synchronization.value());
+  (*repr_)["synchronization"] = synchronization.value();
   return *this;
 }
 
@@ -18874,7 +18545,7 @@ auto TextDocumentClientCapabilities::filters(
     repr_->erase("filters");
     return *this;
   }
-  repr_->emplace("filters", filters.value());
+  (*repr_)["filters"] = filters.value();
   return *this;
 }
 
@@ -18885,7 +18556,7 @@ auto TextDocumentClientCapabilities::completion(
     repr_->erase("completion");
     return *this;
   }
-  repr_->emplace("completion", completion.value());
+  (*repr_)["completion"] = completion.value();
   return *this;
 }
 
@@ -18896,7 +18567,7 @@ auto TextDocumentClientCapabilities::hover(
     repr_->erase("hover");
     return *this;
   }
-  repr_->emplace("hover", hover.value());
+  (*repr_)["hover"] = hover.value();
   return *this;
 }
 
@@ -18907,7 +18578,7 @@ auto TextDocumentClientCapabilities::signatureHelp(
     repr_->erase("signatureHelp");
     return *this;
   }
-  repr_->emplace("signatureHelp", signatureHelp.value());
+  (*repr_)["signatureHelp"] = signatureHelp.value();
   return *this;
 }
 
@@ -18918,7 +18589,7 @@ auto TextDocumentClientCapabilities::declaration(
     repr_->erase("declaration");
     return *this;
   }
-  repr_->emplace("declaration", declaration.value());
+  (*repr_)["declaration"] = declaration.value();
   return *this;
 }
 
@@ -18929,7 +18600,7 @@ auto TextDocumentClientCapabilities::definition(
     repr_->erase("definition");
     return *this;
   }
-  repr_->emplace("definition", definition.value());
+  (*repr_)["definition"] = definition.value();
   return *this;
 }
 
@@ -18940,7 +18611,7 @@ auto TextDocumentClientCapabilities::typeDefinition(
     repr_->erase("typeDefinition");
     return *this;
   }
-  repr_->emplace("typeDefinition", typeDefinition.value());
+  (*repr_)["typeDefinition"] = typeDefinition.value();
   return *this;
 }
 
@@ -18951,7 +18622,7 @@ auto TextDocumentClientCapabilities::implementation(
     repr_->erase("implementation");
     return *this;
   }
-  repr_->emplace("implementation", implementation.value());
+  (*repr_)["implementation"] = implementation.value();
   return *this;
 }
 
@@ -18962,7 +18633,7 @@ auto TextDocumentClientCapabilities::references(
     repr_->erase("references");
     return *this;
   }
-  repr_->emplace("references", references.value());
+  (*repr_)["references"] = references.value();
   return *this;
 }
 
@@ -18973,7 +18644,7 @@ auto TextDocumentClientCapabilities::documentHighlight(
     repr_->erase("documentHighlight");
     return *this;
   }
-  repr_->emplace("documentHighlight", documentHighlight.value());
+  (*repr_)["documentHighlight"] = documentHighlight.value();
   return *this;
 }
 
@@ -18984,7 +18655,7 @@ auto TextDocumentClientCapabilities::documentSymbol(
     repr_->erase("documentSymbol");
     return *this;
   }
-  repr_->emplace("documentSymbol", documentSymbol.value());
+  (*repr_)["documentSymbol"] = documentSymbol.value();
   return *this;
 }
 
@@ -18995,7 +18666,7 @@ auto TextDocumentClientCapabilities::codeAction(
     repr_->erase("codeAction");
     return *this;
   }
-  repr_->emplace("codeAction", codeAction.value());
+  (*repr_)["codeAction"] = codeAction.value();
   return *this;
 }
 
@@ -19006,7 +18677,7 @@ auto TextDocumentClientCapabilities::codeLens(
     repr_->erase("codeLens");
     return *this;
   }
-  repr_->emplace("codeLens", codeLens.value());
+  (*repr_)["codeLens"] = codeLens.value();
   return *this;
 }
 
@@ -19017,7 +18688,7 @@ auto TextDocumentClientCapabilities::documentLink(
     repr_->erase("documentLink");
     return *this;
   }
-  repr_->emplace("documentLink", documentLink.value());
+  (*repr_)["documentLink"] = documentLink.value();
   return *this;
 }
 
@@ -19028,7 +18699,7 @@ auto TextDocumentClientCapabilities::colorProvider(
     repr_->erase("colorProvider");
     return *this;
   }
-  repr_->emplace("colorProvider", colorProvider.value());
+  (*repr_)["colorProvider"] = colorProvider.value();
   return *this;
 }
 
@@ -19039,7 +18710,7 @@ auto TextDocumentClientCapabilities::formatting(
     repr_->erase("formatting");
     return *this;
   }
-  repr_->emplace("formatting", formatting.value());
+  (*repr_)["formatting"] = formatting.value();
   return *this;
 }
 
@@ -19050,7 +18721,7 @@ auto TextDocumentClientCapabilities::rangeFormatting(
     repr_->erase("rangeFormatting");
     return *this;
   }
-  repr_->emplace("rangeFormatting", rangeFormatting.value());
+  (*repr_)["rangeFormatting"] = rangeFormatting.value();
   return *this;
 }
 
@@ -19061,7 +18732,7 @@ auto TextDocumentClientCapabilities::onTypeFormatting(
     repr_->erase("onTypeFormatting");
     return *this;
   }
-  repr_->emplace("onTypeFormatting", onTypeFormatting.value());
+  (*repr_)["onTypeFormatting"] = onTypeFormatting.value();
   return *this;
 }
 
@@ -19072,7 +18743,7 @@ auto TextDocumentClientCapabilities::rename(
     repr_->erase("rename");
     return *this;
   }
-  repr_->emplace("rename", rename.value());
+  (*repr_)["rename"] = rename.value();
   return *this;
 }
 
@@ -19083,7 +18754,7 @@ auto TextDocumentClientCapabilities::foldingRange(
     repr_->erase("foldingRange");
     return *this;
   }
-  repr_->emplace("foldingRange", foldingRange.value());
+  (*repr_)["foldingRange"] = foldingRange.value();
   return *this;
 }
 
@@ -19094,7 +18765,7 @@ auto TextDocumentClientCapabilities::selectionRange(
     repr_->erase("selectionRange");
     return *this;
   }
-  repr_->emplace("selectionRange", selectionRange.value());
+  (*repr_)["selectionRange"] = selectionRange.value();
   return *this;
 }
 
@@ -19105,7 +18776,7 @@ auto TextDocumentClientCapabilities::publishDiagnostics(
     repr_->erase("publishDiagnostics");
     return *this;
   }
-  repr_->emplace("publishDiagnostics", publishDiagnostics.value());
+  (*repr_)["publishDiagnostics"] = publishDiagnostics.value();
   return *this;
 }
 
@@ -19116,7 +18787,7 @@ auto TextDocumentClientCapabilities::callHierarchy(
     repr_->erase("callHierarchy");
     return *this;
   }
-  repr_->emplace("callHierarchy", callHierarchy.value());
+  (*repr_)["callHierarchy"] = callHierarchy.value();
   return *this;
 }
 
@@ -19127,7 +18798,7 @@ auto TextDocumentClientCapabilities::semanticTokens(
     repr_->erase("semanticTokens");
     return *this;
   }
-  repr_->emplace("semanticTokens", semanticTokens.value());
+  (*repr_)["semanticTokens"] = semanticTokens.value();
   return *this;
 }
 
@@ -19138,7 +18809,7 @@ auto TextDocumentClientCapabilities::linkedEditingRange(
     repr_->erase("linkedEditingRange");
     return *this;
   }
-  repr_->emplace("linkedEditingRange", linkedEditingRange.value());
+  (*repr_)["linkedEditingRange"] = linkedEditingRange.value();
   return *this;
 }
 
@@ -19149,7 +18820,7 @@ auto TextDocumentClientCapabilities::moniker(
     repr_->erase("moniker");
     return *this;
   }
-  repr_->emplace("moniker", moniker.value());
+  (*repr_)["moniker"] = moniker.value();
   return *this;
 }
 
@@ -19160,7 +18831,7 @@ auto TextDocumentClientCapabilities::typeHierarchy(
     repr_->erase("typeHierarchy");
     return *this;
   }
-  repr_->emplace("typeHierarchy", typeHierarchy.value());
+  (*repr_)["typeHierarchy"] = typeHierarchy.value();
   return *this;
 }
 
@@ -19171,7 +18842,7 @@ auto TextDocumentClientCapabilities::inlineValue(
     repr_->erase("inlineValue");
     return *this;
   }
-  repr_->emplace("inlineValue", inlineValue.value());
+  (*repr_)["inlineValue"] = inlineValue.value();
   return *this;
 }
 
@@ -19182,7 +18853,7 @@ auto TextDocumentClientCapabilities::inlayHint(
     repr_->erase("inlayHint");
     return *this;
   }
-  repr_->emplace("inlayHint", inlayHint.value());
+  (*repr_)["inlayHint"] = inlayHint.value();
   return *this;
 }
 
@@ -19193,7 +18864,7 @@ auto TextDocumentClientCapabilities::diagnostic(
     repr_->erase("diagnostic");
     return *this;
   }
-  repr_->emplace("diagnostic", diagnostic.value());
+  (*repr_)["diagnostic"] = diagnostic.value();
   return *this;
 }
 
@@ -19204,7 +18875,7 @@ auto TextDocumentClientCapabilities::inlineCompletion(
     repr_->erase("inlineCompletion");
     return *this;
   }
-  repr_->emplace("inlineCompletion", inlineCompletion.value());
+  (*repr_)["inlineCompletion"] = inlineCompletion.value();
   return *this;
 }
 
@@ -19224,7 +18895,7 @@ auto NotebookDocumentClientCapabilities::synchronization() const
 auto NotebookDocumentClientCapabilities::synchronization(
     NotebookDocumentSyncClientCapabilities synchronization)
     -> NotebookDocumentClientCapabilities& {
-  repr_->emplace("synchronization", synchronization);
+  (*repr_)["synchronization"] = synchronization;
   return *this;
 }
 
@@ -19238,6 +18909,7 @@ auto WindowClientCapabilities::workDoneProgress() const -> std::optional<bool> {
 
   auto& value = (*repr_)["workDoneProgress"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -19266,7 +18938,7 @@ auto WindowClientCapabilities::workDoneProgress(
     repr_->erase("workDoneProgress");
     return *this;
   }
-  repr_->emplace("workDoneProgress", std::move(workDoneProgress.value()));
+  (*repr_)["workDoneProgress"] = std::move(workDoneProgress.value());
   return *this;
 }
 
@@ -19277,7 +18949,7 @@ auto WindowClientCapabilities::showMessage(
     repr_->erase("showMessage");
     return *this;
   }
-  repr_->emplace("showMessage", showMessage.value());
+  (*repr_)["showMessage"] = showMessage.value();
   return *this;
 }
 
@@ -19288,7 +18960,7 @@ auto WindowClientCapabilities::showDocument(
     repr_->erase("showDocument");
     return *this;
   }
-  repr_->emplace("showDocument", showDocument.value());
+  (*repr_)["showDocument"] = showDocument.value();
   return *this;
 }
 
@@ -19330,7 +19002,7 @@ auto GeneralClientCapabilities::positionEncodings() const
 
   auto& value = (*repr_)["positionEncodings"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<PositionEncodingKind>(value);
 }
 
@@ -19341,7 +19013,7 @@ auto GeneralClientCapabilities::staleRequestSupport(
     repr_->erase("staleRequestSupport");
     return *this;
   }
-  repr_->emplace("staleRequestSupport", staleRequestSupport.value());
+  (*repr_)["staleRequestSupport"] = staleRequestSupport.value();
   return *this;
 }
 
@@ -19352,7 +19024,7 @@ auto GeneralClientCapabilities::regularExpressions(
     repr_->erase("regularExpressions");
     return *this;
   }
-  repr_->emplace("regularExpressions", regularExpressions.value());
+  (*repr_)["regularExpressions"] = regularExpressions.value();
   return *this;
 }
 
@@ -19363,7 +19035,7 @@ auto GeneralClientCapabilities::markdown(
     repr_->erase("markdown");
     return *this;
   }
-  repr_->emplace("markdown", markdown.value());
+  (*repr_)["markdown"] = markdown.value();
   return *this;
 }
 
@@ -19390,17 +19062,18 @@ auto WorkspaceFoldersServerCapabilities::supported() const
 
   auto& value = (*repr_)["supported"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto WorkspaceFoldersServerCapabilities::changeNotifications() const
-    -> std::optional<std::variant<std::monostate, std::string, bool>> {
+    -> std::optional<std::variant<std::string, bool>> {
   if (!repr_->contains("changeNotifications")) return std::nullopt;
 
   auto& value = (*repr_)["changeNotifications"];
 
-  std::variant<std::monostate, std::string, bool> result;
+  std::variant<std::string, bool> result;
 
   details::try_emplace(result, value);
 
@@ -19413,33 +19086,27 @@ auto WorkspaceFoldersServerCapabilities::supported(
     repr_->erase("supported");
     return *this;
   }
-  repr_->emplace("supported", std::move(supported.value()));
+  (*repr_)["supported"] = std::move(supported.value());
   return *this;
 }
 
 auto WorkspaceFoldersServerCapabilities::changeNotifications(
-    std::optional<std::variant<std::monostate, std::string, bool>>
-        changeNotifications) -> WorkspaceFoldersServerCapabilities& {
+    std::optional<std::variant<std::string, bool>> changeNotifications)
+    -> WorkspaceFoldersServerCapabilities& {
   if (!changeNotifications.has_value()) {
     repr_->erase("changeNotifications");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
     void operator()(std::string changeNotifications) {
-      repr_->emplace("changeNotifications", std::move(changeNotifications));
+      (*repr_)["changeNotifications"] = std::move(changeNotifications);
     }
 
     void operator()(bool changeNotifications) {
-      repr_->emplace("changeNotifications", std::move(changeNotifications));
+      (*repr_)["changeNotifications"] = std::move(changeNotifications);
     }
   } v{repr_};
 
@@ -19514,7 +19181,7 @@ auto FileOperationOptions::didCreate(
     repr_->erase("didCreate");
     return *this;
   }
-  repr_->emplace("didCreate", didCreate.value());
+  (*repr_)["didCreate"] = didCreate.value();
   return *this;
 }
 
@@ -19525,7 +19192,7 @@ auto FileOperationOptions::willCreate(
     repr_->erase("willCreate");
     return *this;
   }
-  repr_->emplace("willCreate", willCreate.value());
+  (*repr_)["willCreate"] = willCreate.value();
   return *this;
 }
 
@@ -19536,7 +19203,7 @@ auto FileOperationOptions::didRename(
     repr_->erase("didRename");
     return *this;
   }
-  repr_->emplace("didRename", didRename.value());
+  (*repr_)["didRename"] = didRename.value();
   return *this;
 }
 
@@ -19547,7 +19214,7 @@ auto FileOperationOptions::willRename(
     repr_->erase("willRename");
     return *this;
   }
-  repr_->emplace("willRename", willRename.value());
+  (*repr_)["willRename"] = willRename.value();
   return *this;
 }
 
@@ -19558,7 +19225,7 @@ auto FileOperationOptions::didDelete(
     repr_->erase("didDelete");
     return *this;
   }
-  repr_->emplace("didDelete", didDelete.value());
+  (*repr_)["didDelete"] = didDelete.value();
   return *this;
 }
 
@@ -19569,7 +19236,7 @@ auto FileOperationOptions::willDelete(
     repr_->erase("willDelete");
     return *this;
   }
-  repr_->emplace("willDelete", willDelete.value());
+  (*repr_)["willDelete"] = willDelete.value();
   return *this;
 }
 
@@ -19581,10 +19248,10 @@ RelativePattern::operator bool() const {
 }
 
 auto RelativePattern::baseUri() const
-    -> std::variant<std::monostate, WorkspaceFolder, std::string> {
+    -> std::variant<WorkspaceFolder, std::string> {
   auto& value = (*repr_)["baseUri"];
 
-  std::variant<std::monostate, WorkspaceFolder, std::string> result;
+  std::variant<WorkspaceFolder, std::string> result;
 
   details::try_emplace(result, value);
 
@@ -19594,28 +19261,20 @@ auto RelativePattern::baseUri() const
 auto RelativePattern::pattern() const -> Pattern {
   auto& value = (*repr_)["pattern"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
 
 auto RelativePattern::baseUri(
-    std::variant<std::monostate, WorkspaceFolder, std::string> baseUri)
-    -> RelativePattern& {
-  // or type
-
+    std::variant<WorkspaceFolder, std::string> baseUri) -> RelativePattern& {
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(WorkspaceFolder baseUri) {
-      repr_->emplace("baseUri", baseUri);
-    }
+    void operator()(WorkspaceFolder baseUri) { (*repr_)["baseUri"] = baseUri; }
 
     void operator()(std::string baseUri) {
-      repr_->emplace("baseUri", std::move(baseUri));
+      (*repr_)["baseUri"] = std::move(baseUri);
     }
   } v{repr_};
 
@@ -19638,6 +19297,7 @@ TextDocumentFilterLanguage::operator bool() const {
 auto TextDocumentFilterLanguage::language() const -> std::string {
   auto& value = (*repr_)["language"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19647,6 +19307,7 @@ auto TextDocumentFilterLanguage::scheme() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["scheme"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19665,7 +19326,7 @@ auto TextDocumentFilterLanguage::pattern() const -> std::optional<GlobPattern> {
 
 auto TextDocumentFilterLanguage::language(std::string language)
     -> TextDocumentFilterLanguage& {
-  repr_->emplace("language", std::move(language));
+  (*repr_)["language"] = std::move(language);
   return *this;
 }
 
@@ -19675,7 +19336,7 @@ auto TextDocumentFilterLanguage::scheme(std::optional<std::string> scheme)
     repr_->erase("scheme");
     return *this;
   }
-  repr_->emplace("scheme", std::move(scheme.value()));
+  (*repr_)["scheme"] = std::move(scheme.value());
   return *this;
 }
 
@@ -19700,6 +19361,7 @@ auto TextDocumentFilterScheme::language() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["language"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19707,6 +19369,7 @@ auto TextDocumentFilterScheme::language() const -> std::optional<std::string> {
 auto TextDocumentFilterScheme::scheme() const -> std::string {
   auto& value = (*repr_)["scheme"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19729,13 +19392,13 @@ auto TextDocumentFilterScheme::language(std::optional<std::string> language)
     repr_->erase("language");
     return *this;
   }
-  repr_->emplace("language", std::move(language.value()));
+  (*repr_)["language"] = std::move(language.value());
   return *this;
 }
 
 auto TextDocumentFilterScheme::scheme(std::string scheme)
     -> TextDocumentFilterScheme& {
-  repr_->emplace("scheme", std::move(scheme));
+  (*repr_)["scheme"] = std::move(scheme);
   return *this;
 }
 
@@ -19760,6 +19423,7 @@ auto TextDocumentFilterPattern::language() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["language"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19769,6 +19433,7 @@ auto TextDocumentFilterPattern::scheme() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["scheme"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19789,7 +19454,7 @@ auto TextDocumentFilterPattern::language(std::optional<std::string> language)
     repr_->erase("language");
     return *this;
   }
-  repr_->emplace("language", std::move(language.value()));
+  (*repr_)["language"] = std::move(language.value());
   return *this;
 }
 
@@ -19799,7 +19464,7 @@ auto TextDocumentFilterPattern::scheme(std::optional<std::string> scheme)
     repr_->erase("scheme");
     return *this;
   }
-  repr_->emplace("scheme", std::move(scheme.value()));
+  (*repr_)["scheme"] = std::move(scheme.value());
   return *this;
 }
 
@@ -19818,6 +19483,7 @@ NotebookDocumentFilterNotebookType::operator bool() const {
 auto NotebookDocumentFilterNotebookType::notebookType() const -> std::string {
   auto& value = (*repr_)["notebookType"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19828,6 +19494,7 @@ auto NotebookDocumentFilterNotebookType::scheme() const
 
   auto& value = (*repr_)["scheme"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19847,7 +19514,7 @@ auto NotebookDocumentFilterNotebookType::pattern() const
 
 auto NotebookDocumentFilterNotebookType::notebookType(std::string notebookType)
     -> NotebookDocumentFilterNotebookType& {
-  repr_->emplace("notebookType", std::move(notebookType));
+  (*repr_)["notebookType"] = std::move(notebookType);
   return *this;
 }
 
@@ -19857,7 +19524,7 @@ auto NotebookDocumentFilterNotebookType::scheme(
     repr_->erase("scheme");
     return *this;
   }
-  repr_->emplace("scheme", std::move(scheme.value()));
+  (*repr_)["scheme"] = std::move(scheme.value());
   return *this;
 }
 
@@ -19884,6 +19551,7 @@ auto NotebookDocumentFilterScheme::notebookType() const
 
   auto& value = (*repr_)["notebookType"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19891,6 +19559,7 @@ auto NotebookDocumentFilterScheme::notebookType() const
 auto NotebookDocumentFilterScheme::scheme() const -> std::string {
   auto& value = (*repr_)["scheme"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19914,13 +19583,13 @@ auto NotebookDocumentFilterScheme::notebookType(
     repr_->erase("notebookType");
     return *this;
   }
-  repr_->emplace("notebookType", std::move(notebookType.value()));
+  (*repr_)["notebookType"] = std::move(notebookType.value());
   return *this;
 }
 
 auto NotebookDocumentFilterScheme::scheme(std::string scheme)
     -> NotebookDocumentFilterScheme& {
-  repr_->emplace("scheme", std::move(scheme));
+  (*repr_)["scheme"] = std::move(scheme);
   return *this;
 }
 
@@ -19946,6 +19615,7 @@ auto NotebookDocumentFilterPattern::notebookType() const
 
   auto& value = (*repr_)["notebookType"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19956,6 +19626,7 @@ auto NotebookDocumentFilterPattern::scheme() const
 
   auto& value = (*repr_)["scheme"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -19976,7 +19647,7 @@ auto NotebookDocumentFilterPattern::notebookType(
     repr_->erase("notebookType");
     return *this;
   }
-  repr_->emplace("notebookType", std::move(notebookType.value()));
+  (*repr_)["notebookType"] = std::move(notebookType.value());
   return *this;
 }
 
@@ -19986,7 +19657,7 @@ auto NotebookDocumentFilterPattern::scheme(std::optional<std::string> scheme)
     repr_->erase("scheme");
     return *this;
   }
-  repr_->emplace("scheme", std::move(scheme.value()));
+  (*repr_)["scheme"] = std::move(scheme.value());
   return *this;
 }
 
@@ -20007,6 +19678,7 @@ NotebookCellArrayChange::operator bool() const {
 auto NotebookCellArrayChange::start() const -> long {
   auto& value = (*repr_)["start"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -20014,6 +19686,7 @@ auto NotebookCellArrayChange::start() const -> long {
 auto NotebookCellArrayChange::deleteCount() const -> long {
   auto& value = (*repr_)["deleteCount"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -20024,18 +19697,18 @@ auto NotebookCellArrayChange::cells() const
 
   auto& value = (*repr_)["cells"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<NotebookCell>(value);
 }
 
 auto NotebookCellArrayChange::start(long start) -> NotebookCellArrayChange& {
-  repr_->emplace("start", std::move(start));
+  (*repr_)["start"] = std::move(start);
   return *this;
 }
 
 auto NotebookCellArrayChange::deleteCount(long deleteCount)
     -> NotebookCellArrayChange& {
-  repr_->emplace("deleteCount", std::move(deleteCount));
+  (*repr_)["deleteCount"] = std::move(deleteCount);
   return *this;
 }
 
@@ -20060,6 +19733,7 @@ auto WorkspaceEditClientCapabilities::documentChanges() const
 
   auto& value = (*repr_)["documentChanges"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20070,7 +19744,7 @@ auto WorkspaceEditClientCapabilities::resourceOperations() const
 
   auto& value = (*repr_)["resourceOperations"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<ResourceOperationKind>(value);
 }
 
@@ -20090,6 +19764,7 @@ auto WorkspaceEditClientCapabilities::normalizesLineEndings() const
 
   auto& value = (*repr_)["normalizesLineEndings"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20109,6 +19784,7 @@ auto WorkspaceEditClientCapabilities::metadataSupport() const
 
   auto& value = (*repr_)["metadataSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20119,6 +19795,7 @@ auto WorkspaceEditClientCapabilities::snippetEditSupport() const
 
   auto& value = (*repr_)["snippetEditSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20129,7 +19806,7 @@ auto WorkspaceEditClientCapabilities::documentChanges(
     repr_->erase("documentChanges");
     return *this;
   }
-  repr_->emplace("documentChanges", std::move(documentChanges.value()));
+  (*repr_)["documentChanges"] = std::move(documentChanges.value());
   return *this;
 }
 
@@ -20164,8 +19841,7 @@ auto WorkspaceEditClientCapabilities::normalizesLineEndings(
     repr_->erase("normalizesLineEndings");
     return *this;
   }
-  repr_->emplace("normalizesLineEndings",
-                 std::move(normalizesLineEndings.value()));
+  (*repr_)["normalizesLineEndings"] = std::move(normalizesLineEndings.value());
   return *this;
 }
 
@@ -20176,7 +19852,7 @@ auto WorkspaceEditClientCapabilities::changeAnnotationSupport(
     repr_->erase("changeAnnotationSupport");
     return *this;
   }
-  repr_->emplace("changeAnnotationSupport", changeAnnotationSupport.value());
+  (*repr_)["changeAnnotationSupport"] = changeAnnotationSupport.value();
   return *this;
 }
 
@@ -20186,7 +19862,7 @@ auto WorkspaceEditClientCapabilities::metadataSupport(
     repr_->erase("metadataSupport");
     return *this;
   }
-  repr_->emplace("metadataSupport", std::move(metadataSupport.value()));
+  (*repr_)["metadataSupport"] = std::move(metadataSupport.value());
   return *this;
 }
 
@@ -20197,7 +19873,7 @@ auto WorkspaceEditClientCapabilities::snippetEditSupport(
     repr_->erase("snippetEditSupport");
     return *this;
   }
-  repr_->emplace("snippetEditSupport", std::move(snippetEditSupport.value()));
+  (*repr_)["snippetEditSupport"] = std::move(snippetEditSupport.value());
   return *this;
 }
 
@@ -20212,6 +19888,7 @@ auto DidChangeConfigurationClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20223,7 +19900,7 @@ auto DidChangeConfigurationClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -20238,6 +19915,7 @@ auto DidChangeWatchedFilesClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20248,6 +19926,7 @@ auto DidChangeWatchedFilesClientCapabilities::relativePatternSupport() const
 
   auto& value = (*repr_)["relativePatternSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20259,7 +19938,7 @@ auto DidChangeWatchedFilesClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -20270,8 +19949,8 @@ auto DidChangeWatchedFilesClientCapabilities::relativePatternSupport(
     repr_->erase("relativePatternSupport");
     return *this;
   }
-  repr_->emplace("relativePatternSupport",
-                 std::move(relativePatternSupport.value()));
+  (*repr_)["relativePatternSupport"] =
+      std::move(relativePatternSupport.value());
   return *this;
 }
 
@@ -20286,6 +19965,7 @@ auto WorkspaceSymbolClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20324,7 +20004,7 @@ auto WorkspaceSymbolClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -20335,7 +20015,7 @@ auto WorkspaceSymbolClientCapabilities::symbolKind(
     repr_->erase("symbolKind");
     return *this;
   }
-  repr_->emplace("symbolKind", symbolKind.value());
+  (*repr_)["symbolKind"] = symbolKind.value();
   return *this;
 }
 
@@ -20346,7 +20026,7 @@ auto WorkspaceSymbolClientCapabilities::tagSupport(
     repr_->erase("tagSupport");
     return *this;
   }
-  repr_->emplace("tagSupport", tagSupport.value());
+  (*repr_)["tagSupport"] = tagSupport.value();
   return *this;
 }
 
@@ -20357,7 +20037,7 @@ auto WorkspaceSymbolClientCapabilities::resolveSupport(
     repr_->erase("resolveSupport");
     return *this;
   }
-  repr_->emplace("resolveSupport", resolveSupport.value());
+  (*repr_)["resolveSupport"] = resolveSupport.value();
   return *this;
 }
 
@@ -20372,6 +20052,7 @@ auto ExecuteCommandClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20383,7 +20064,7 @@ auto ExecuteCommandClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -20398,6 +20079,7 @@ auto SemanticTokensWorkspaceClientCapabilities::refreshSupport() const
 
   auto& value = (*repr_)["refreshSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20409,7 +20091,7 @@ auto SemanticTokensWorkspaceClientCapabilities::refreshSupport(
     repr_->erase("refreshSupport");
     return *this;
   }
-  repr_->emplace("refreshSupport", std::move(refreshSupport.value()));
+  (*repr_)["refreshSupport"] = std::move(refreshSupport.value());
   return *this;
 }
 
@@ -20424,6 +20106,7 @@ auto CodeLensWorkspaceClientCapabilities::refreshSupport() const
 
   auto& value = (*repr_)["refreshSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20435,7 +20118,7 @@ auto CodeLensWorkspaceClientCapabilities::refreshSupport(
     repr_->erase("refreshSupport");
     return *this;
   }
-  repr_->emplace("refreshSupport", std::move(refreshSupport.value()));
+  (*repr_)["refreshSupport"] = std::move(refreshSupport.value());
   return *this;
 }
 
@@ -20450,6 +20133,7 @@ auto FileOperationClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20459,6 +20143,7 @@ auto FileOperationClientCapabilities::didCreate() const -> std::optional<bool> {
 
   auto& value = (*repr_)["didCreate"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20469,6 +20154,7 @@ auto FileOperationClientCapabilities::willCreate() const
 
   auto& value = (*repr_)["willCreate"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20478,6 +20164,7 @@ auto FileOperationClientCapabilities::didRename() const -> std::optional<bool> {
 
   auto& value = (*repr_)["didRename"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20488,6 +20175,7 @@ auto FileOperationClientCapabilities::willRename() const
 
   auto& value = (*repr_)["willRename"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20497,6 +20185,7 @@ auto FileOperationClientCapabilities::didDelete() const -> std::optional<bool> {
 
   auto& value = (*repr_)["didDelete"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20507,6 +20196,7 @@ auto FileOperationClientCapabilities::willDelete() const
 
   auto& value = (*repr_)["willDelete"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20518,7 +20208,7 @@ auto FileOperationClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -20528,7 +20218,7 @@ auto FileOperationClientCapabilities::didCreate(std::optional<bool> didCreate)
     repr_->erase("didCreate");
     return *this;
   }
-  repr_->emplace("didCreate", std::move(didCreate.value()));
+  (*repr_)["didCreate"] = std::move(didCreate.value());
   return *this;
 }
 
@@ -20538,7 +20228,7 @@ auto FileOperationClientCapabilities::willCreate(std::optional<bool> willCreate)
     repr_->erase("willCreate");
     return *this;
   }
-  repr_->emplace("willCreate", std::move(willCreate.value()));
+  (*repr_)["willCreate"] = std::move(willCreate.value());
   return *this;
 }
 
@@ -20548,7 +20238,7 @@ auto FileOperationClientCapabilities::didRename(std::optional<bool> didRename)
     repr_->erase("didRename");
     return *this;
   }
-  repr_->emplace("didRename", std::move(didRename.value()));
+  (*repr_)["didRename"] = std::move(didRename.value());
   return *this;
 }
 
@@ -20558,7 +20248,7 @@ auto FileOperationClientCapabilities::willRename(std::optional<bool> willRename)
     repr_->erase("willRename");
     return *this;
   }
-  repr_->emplace("willRename", std::move(willRename.value()));
+  (*repr_)["willRename"] = std::move(willRename.value());
   return *this;
 }
 
@@ -20568,7 +20258,7 @@ auto FileOperationClientCapabilities::didDelete(std::optional<bool> didDelete)
     repr_->erase("didDelete");
     return *this;
   }
-  repr_->emplace("didDelete", std::move(didDelete.value()));
+  (*repr_)["didDelete"] = std::move(didDelete.value());
   return *this;
 }
 
@@ -20578,7 +20268,7 @@ auto FileOperationClientCapabilities::willDelete(std::optional<bool> willDelete)
     repr_->erase("willDelete");
     return *this;
   }
-  repr_->emplace("willDelete", std::move(willDelete.value()));
+  (*repr_)["willDelete"] = std::move(willDelete.value());
   return *this;
 }
 
@@ -20593,6 +20283,7 @@ auto InlineValueWorkspaceClientCapabilities::refreshSupport() const
 
   auto& value = (*repr_)["refreshSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20604,7 +20295,7 @@ auto InlineValueWorkspaceClientCapabilities::refreshSupport(
     repr_->erase("refreshSupport");
     return *this;
   }
-  repr_->emplace("refreshSupport", std::move(refreshSupport.value()));
+  (*repr_)["refreshSupport"] = std::move(refreshSupport.value());
   return *this;
 }
 
@@ -20619,6 +20310,7 @@ auto InlayHintWorkspaceClientCapabilities::refreshSupport() const
 
   auto& value = (*repr_)["refreshSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20630,7 +20322,7 @@ auto InlayHintWorkspaceClientCapabilities::refreshSupport(
     repr_->erase("refreshSupport");
     return *this;
   }
-  repr_->emplace("refreshSupport", std::move(refreshSupport.value()));
+  (*repr_)["refreshSupport"] = std::move(refreshSupport.value());
   return *this;
 }
 
@@ -20645,6 +20337,7 @@ auto DiagnosticWorkspaceClientCapabilities::refreshSupport() const
 
   auto& value = (*repr_)["refreshSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20656,7 +20349,7 @@ auto DiagnosticWorkspaceClientCapabilities::refreshSupport(
     repr_->erase("refreshSupport");
     return *this;
   }
-  repr_->emplace("refreshSupport", std::move(refreshSupport.value()));
+  (*repr_)["refreshSupport"] = std::move(refreshSupport.value());
   return *this;
 }
 
@@ -20671,6 +20364,7 @@ auto FoldingRangeWorkspaceClientCapabilities::refreshSupport() const
 
   auto& value = (*repr_)["refreshSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20682,7 +20376,7 @@ auto FoldingRangeWorkspaceClientCapabilities::refreshSupport(
     repr_->erase("refreshSupport");
     return *this;
   }
-  repr_->emplace("refreshSupport", std::move(refreshSupport.value()));
+  (*repr_)["refreshSupport"] = std::move(refreshSupport.value());
   return *this;
 }
 
@@ -20697,6 +20391,7 @@ auto TextDocumentContentClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20708,7 +20403,7 @@ auto TextDocumentContentClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -20723,6 +20418,7 @@ auto TextDocumentSyncClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20733,6 +20429,7 @@ auto TextDocumentSyncClientCapabilities::willSave() const
 
   auto& value = (*repr_)["willSave"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20743,6 +20440,7 @@ auto TextDocumentSyncClientCapabilities::willSaveWaitUntil() const
 
   auto& value = (*repr_)["willSaveWaitUntil"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20753,6 +20451,7 @@ auto TextDocumentSyncClientCapabilities::didSave() const
 
   auto& value = (*repr_)["didSave"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20764,7 +20463,7 @@ auto TextDocumentSyncClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -20774,7 +20473,7 @@ auto TextDocumentSyncClientCapabilities::willSave(std::optional<bool> willSave)
     repr_->erase("willSave");
     return *this;
   }
-  repr_->emplace("willSave", std::move(willSave.value()));
+  (*repr_)["willSave"] = std::move(willSave.value());
   return *this;
 }
 
@@ -20785,7 +20484,7 @@ auto TextDocumentSyncClientCapabilities::willSaveWaitUntil(
     repr_->erase("willSaveWaitUntil");
     return *this;
   }
-  repr_->emplace("willSaveWaitUntil", std::move(willSaveWaitUntil.value()));
+  (*repr_)["willSaveWaitUntil"] = std::move(willSaveWaitUntil.value());
   return *this;
 }
 
@@ -20795,7 +20494,7 @@ auto TextDocumentSyncClientCapabilities::didSave(std::optional<bool> didSave)
     repr_->erase("didSave");
     return *this;
   }
-  repr_->emplace("didSave", std::move(didSave.value()));
+  (*repr_)["didSave"] = std::move(didSave.value());
   return *this;
 }
 
@@ -20810,6 +20509,7 @@ auto TextDocumentFilterClientCapabilities::relativePatternSupport() const
 
   auto& value = (*repr_)["relativePatternSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20821,8 +20521,8 @@ auto TextDocumentFilterClientCapabilities::relativePatternSupport(
     repr_->erase("relativePatternSupport");
     return *this;
   }
-  repr_->emplace("relativePatternSupport",
-                 std::move(relativePatternSupport.value()));
+  (*repr_)["relativePatternSupport"] =
+      std::move(relativePatternSupport.value());
   return *this;
 }
 
@@ -20837,6 +20537,7 @@ auto CompletionClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20874,6 +20575,7 @@ auto CompletionClientCapabilities::contextSupport() const
 
   auto& value = (*repr_)["contextSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20893,7 +20595,7 @@ auto CompletionClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -20904,7 +20606,7 @@ auto CompletionClientCapabilities::completionItem(
     repr_->erase("completionItem");
     return *this;
   }
-  repr_->emplace("completionItem", completionItem.value());
+  (*repr_)["completionItem"] = completionItem.value();
   return *this;
 }
 
@@ -20915,7 +20617,7 @@ auto CompletionClientCapabilities::completionItemKind(
     repr_->erase("completionItemKind");
     return *this;
   }
-  repr_->emplace("completionItemKind", completionItemKind.value());
+  (*repr_)["completionItemKind"] = completionItemKind.value();
   return *this;
 }
 
@@ -20926,7 +20628,7 @@ auto CompletionClientCapabilities::insertTextMode(
     repr_->erase("insertTextMode");
     return *this;
   }
-  repr_->emplace("insertTextMode", static_cast<long>(insertTextMode.value()));
+  (*repr_)["insertTextMode"] = static_cast<long>(insertTextMode.value());
   return *this;
 }
 
@@ -20936,7 +20638,7 @@ auto CompletionClientCapabilities::contextSupport(
     repr_->erase("contextSupport");
     return *this;
   }
-  repr_->emplace("contextSupport", std::move(contextSupport.value()));
+  (*repr_)["contextSupport"] = std::move(contextSupport.value());
   return *this;
 }
 
@@ -20947,7 +20649,7 @@ auto CompletionClientCapabilities::completionList(
     repr_->erase("completionList");
     return *this;
   }
-  repr_->emplace("completionList", completionList.value());
+  (*repr_)["completionList"] = completionList.value();
   return *this;
 }
 
@@ -20962,6 +20664,7 @@ auto HoverClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -20972,7 +20675,7 @@ auto HoverClientCapabilities::contentFormat() const
 
   auto& value = (*repr_)["contentFormat"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<MarkupKind>(value);
 }
 
@@ -20982,7 +20685,7 @@ auto HoverClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21009,6 +20712,7 @@ auto SignatureHelpClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21028,6 +20732,7 @@ auto SignatureHelpClientCapabilities::contextSupport() const
 
   auto& value = (*repr_)["contextSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21039,7 +20744,7 @@ auto SignatureHelpClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21050,7 +20755,7 @@ auto SignatureHelpClientCapabilities::signatureInformation(
     repr_->erase("signatureInformation");
     return *this;
   }
-  repr_->emplace("signatureInformation", signatureInformation.value());
+  (*repr_)["signatureInformation"] = signatureInformation.value();
   return *this;
 }
 
@@ -21060,7 +20765,7 @@ auto SignatureHelpClientCapabilities::contextSupport(
     repr_->erase("contextSupport");
     return *this;
   }
-  repr_->emplace("contextSupport", std::move(contextSupport.value()));
+  (*repr_)["contextSupport"] = std::move(contextSupport.value());
   return *this;
 }
 
@@ -21075,6 +20780,7 @@ auto DeclarationClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21084,6 +20790,7 @@ auto DeclarationClientCapabilities::linkSupport() const -> std::optional<bool> {
 
   auto& value = (*repr_)["linkSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21094,7 +20801,7 @@ auto DeclarationClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21104,7 +20811,7 @@ auto DeclarationClientCapabilities::linkSupport(std::optional<bool> linkSupport)
     repr_->erase("linkSupport");
     return *this;
   }
-  repr_->emplace("linkSupport", std::move(linkSupport.value()));
+  (*repr_)["linkSupport"] = std::move(linkSupport.value());
   return *this;
 }
 
@@ -21119,6 +20826,7 @@ auto DefinitionClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21128,6 +20836,7 @@ auto DefinitionClientCapabilities::linkSupport() const -> std::optional<bool> {
 
   auto& value = (*repr_)["linkSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21138,7 +20847,7 @@ auto DefinitionClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21148,7 +20857,7 @@ auto DefinitionClientCapabilities::linkSupport(std::optional<bool> linkSupport)
     repr_->erase("linkSupport");
     return *this;
   }
-  repr_->emplace("linkSupport", std::move(linkSupport.value()));
+  (*repr_)["linkSupport"] = std::move(linkSupport.value());
   return *this;
 }
 
@@ -21163,6 +20872,7 @@ auto TypeDefinitionClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21173,6 +20883,7 @@ auto TypeDefinitionClientCapabilities::linkSupport() const
 
   auto& value = (*repr_)["linkSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21184,7 +20895,7 @@ auto TypeDefinitionClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21194,7 +20905,7 @@ auto TypeDefinitionClientCapabilities::linkSupport(
     repr_->erase("linkSupport");
     return *this;
   }
-  repr_->emplace("linkSupport", std::move(linkSupport.value()));
+  (*repr_)["linkSupport"] = std::move(linkSupport.value());
   return *this;
 }
 
@@ -21209,6 +20920,7 @@ auto ImplementationClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21219,6 +20931,7 @@ auto ImplementationClientCapabilities::linkSupport() const
 
   auto& value = (*repr_)["linkSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21230,7 +20943,7 @@ auto ImplementationClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21240,7 +20953,7 @@ auto ImplementationClientCapabilities::linkSupport(
     repr_->erase("linkSupport");
     return *this;
   }
-  repr_->emplace("linkSupport", std::move(linkSupport.value()));
+  (*repr_)["linkSupport"] = std::move(linkSupport.value());
   return *this;
 }
 
@@ -21255,6 +20968,7 @@ auto ReferenceClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21265,7 +20979,7 @@ auto ReferenceClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21280,6 +20994,7 @@ auto DocumentHighlightClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21291,7 +21006,7 @@ auto DocumentHighlightClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21306,6 +21021,7 @@ auto DocumentSymbolClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21326,6 +21042,7 @@ auto DocumentSymbolClientCapabilities::hierarchicalDocumentSymbolSupport() const
 
   auto& value = (*repr_)["hierarchicalDocumentSymbolSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21345,6 +21062,7 @@ auto DocumentSymbolClientCapabilities::labelSupport() const
 
   auto& value = (*repr_)["labelSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21356,7 +21074,7 @@ auto DocumentSymbolClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21367,7 +21085,7 @@ auto DocumentSymbolClientCapabilities::symbolKind(
     repr_->erase("symbolKind");
     return *this;
   }
-  repr_->emplace("symbolKind", symbolKind.value());
+  (*repr_)["symbolKind"] = symbolKind.value();
   return *this;
 }
 
@@ -21378,8 +21096,8 @@ auto DocumentSymbolClientCapabilities::hierarchicalDocumentSymbolSupport(
     repr_->erase("hierarchicalDocumentSymbolSupport");
     return *this;
   }
-  repr_->emplace("hierarchicalDocumentSymbolSupport",
-                 std::move(hierarchicalDocumentSymbolSupport.value()));
+  (*repr_)["hierarchicalDocumentSymbolSupport"] =
+      std::move(hierarchicalDocumentSymbolSupport.value());
   return *this;
 }
 
@@ -21390,7 +21108,7 @@ auto DocumentSymbolClientCapabilities::tagSupport(
     repr_->erase("tagSupport");
     return *this;
   }
-  repr_->emplace("tagSupport", tagSupport.value());
+  (*repr_)["tagSupport"] = tagSupport.value();
   return *this;
 }
 
@@ -21400,7 +21118,7 @@ auto DocumentSymbolClientCapabilities::labelSupport(
     repr_->erase("labelSupport");
     return *this;
   }
-  repr_->emplace("labelSupport", std::move(labelSupport.value()));
+  (*repr_)["labelSupport"] = std::move(labelSupport.value());
   return *this;
 }
 
@@ -21415,6 +21133,7 @@ auto CodeActionClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21434,6 +21153,7 @@ auto CodeActionClientCapabilities::isPreferredSupport() const
 
   auto& value = (*repr_)["isPreferredSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21444,6 +21164,7 @@ auto CodeActionClientCapabilities::disabledSupport() const
 
   auto& value = (*repr_)["disabledSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21453,6 +21174,7 @@ auto CodeActionClientCapabilities::dataSupport() const -> std::optional<bool> {
 
   auto& value = (*repr_)["dataSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21472,6 +21194,7 @@ auto CodeActionClientCapabilities::honorsChangeAnnotations() const
 
   auto& value = (*repr_)["honorsChangeAnnotations"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21482,6 +21205,7 @@ auto CodeActionClientCapabilities::documentationSupport() const
 
   auto& value = (*repr_)["documentationSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21501,7 +21225,7 @@ auto CodeActionClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21512,7 +21236,7 @@ auto CodeActionClientCapabilities::codeActionLiteralSupport(
     repr_->erase("codeActionLiteralSupport");
     return *this;
   }
-  repr_->emplace("codeActionLiteralSupport", codeActionLiteralSupport.value());
+  (*repr_)["codeActionLiteralSupport"] = codeActionLiteralSupport.value();
   return *this;
 }
 
@@ -21522,7 +21246,7 @@ auto CodeActionClientCapabilities::isPreferredSupport(
     repr_->erase("isPreferredSupport");
     return *this;
   }
-  repr_->emplace("isPreferredSupport", std::move(isPreferredSupport.value()));
+  (*repr_)["isPreferredSupport"] = std::move(isPreferredSupport.value());
   return *this;
 }
 
@@ -21532,7 +21256,7 @@ auto CodeActionClientCapabilities::disabledSupport(
     repr_->erase("disabledSupport");
     return *this;
   }
-  repr_->emplace("disabledSupport", std::move(disabledSupport.value()));
+  (*repr_)["disabledSupport"] = std::move(disabledSupport.value());
   return *this;
 }
 
@@ -21542,7 +21266,7 @@ auto CodeActionClientCapabilities::dataSupport(std::optional<bool> dataSupport)
     repr_->erase("dataSupport");
     return *this;
   }
-  repr_->emplace("dataSupport", std::move(dataSupport.value()));
+  (*repr_)["dataSupport"] = std::move(dataSupport.value());
   return *this;
 }
 
@@ -21553,7 +21277,7 @@ auto CodeActionClientCapabilities::resolveSupport(
     repr_->erase("resolveSupport");
     return *this;
   }
-  repr_->emplace("resolveSupport", resolveSupport.value());
+  (*repr_)["resolveSupport"] = resolveSupport.value();
   return *this;
 }
 
@@ -21564,8 +21288,8 @@ auto CodeActionClientCapabilities::honorsChangeAnnotations(
     repr_->erase("honorsChangeAnnotations");
     return *this;
   }
-  repr_->emplace("honorsChangeAnnotations",
-                 std::move(honorsChangeAnnotations.value()));
+  (*repr_)["honorsChangeAnnotations"] =
+      std::move(honorsChangeAnnotations.value());
   return *this;
 }
 
@@ -21575,8 +21299,7 @@ auto CodeActionClientCapabilities::documentationSupport(
     repr_->erase("documentationSupport");
     return *this;
   }
-  repr_->emplace("documentationSupport",
-                 std::move(documentationSupport.value()));
+  (*repr_)["documentationSupport"] = std::move(documentationSupport.value());
   return *this;
 }
 
@@ -21587,7 +21310,7 @@ auto CodeActionClientCapabilities::tagSupport(
     repr_->erase("tagSupport");
     return *this;
   }
-  repr_->emplace("tagSupport", tagSupport.value());
+  (*repr_)["tagSupport"] = tagSupport.value();
   return *this;
 }
 
@@ -21602,6 +21325,7 @@ auto CodeLensClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21621,7 +21345,7 @@ auto CodeLensClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21632,7 +21356,7 @@ auto CodeLensClientCapabilities::resolveSupport(
     repr_->erase("resolveSupport");
     return *this;
   }
-  repr_->emplace("resolveSupport", resolveSupport.value());
+  (*repr_)["resolveSupport"] = resolveSupport.value();
   return *this;
 }
 
@@ -21647,6 +21371,7 @@ auto DocumentLinkClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21657,6 +21382,7 @@ auto DocumentLinkClientCapabilities::tooltipSupport() const
 
   auto& value = (*repr_)["tooltipSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21668,7 +21394,7 @@ auto DocumentLinkClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21678,7 +21404,7 @@ auto DocumentLinkClientCapabilities::tooltipSupport(
     repr_->erase("tooltipSupport");
     return *this;
   }
-  repr_->emplace("tooltipSupport", std::move(tooltipSupport.value()));
+  (*repr_)["tooltipSupport"] = std::move(tooltipSupport.value());
   return *this;
 }
 
@@ -21693,6 +21419,7 @@ auto DocumentColorClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21704,7 +21431,7 @@ auto DocumentColorClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21719,6 +21446,7 @@ auto DocumentFormattingClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21730,7 +21458,7 @@ auto DocumentFormattingClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21745,6 +21473,7 @@ auto DocumentRangeFormattingClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21755,6 +21484,7 @@ auto DocumentRangeFormattingClientCapabilities::rangesSupport() const
 
   auto& value = (*repr_)["rangesSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21766,7 +21496,7 @@ auto DocumentRangeFormattingClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21777,7 +21507,7 @@ auto DocumentRangeFormattingClientCapabilities::rangesSupport(
     repr_->erase("rangesSupport");
     return *this;
   }
-  repr_->emplace("rangesSupport", std::move(rangesSupport.value()));
+  (*repr_)["rangesSupport"] = std::move(rangesSupport.value());
   return *this;
 }
 
@@ -21792,6 +21522,7 @@ auto DocumentOnTypeFormattingClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21803,7 +21534,7 @@ auto DocumentOnTypeFormattingClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21818,6 +21549,7 @@ auto RenameClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21827,6 +21559,7 @@ auto RenameClientCapabilities::prepareSupport() const -> std::optional<bool> {
 
   auto& value = (*repr_)["prepareSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21846,6 +21579,7 @@ auto RenameClientCapabilities::honorsChangeAnnotations() const
 
   auto& value = (*repr_)["honorsChangeAnnotations"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21856,7 +21590,7 @@ auto RenameClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21866,7 +21600,7 @@ auto RenameClientCapabilities::prepareSupport(
     repr_->erase("prepareSupport");
     return *this;
   }
-  repr_->emplace("prepareSupport", std::move(prepareSupport.value()));
+  (*repr_)["prepareSupport"] = std::move(prepareSupport.value());
   return *this;
 }
 
@@ -21877,8 +21611,8 @@ auto RenameClientCapabilities::prepareSupportDefaultBehavior(
     repr_->erase("prepareSupportDefaultBehavior");
     return *this;
   }
-  repr_->emplace("prepareSupportDefaultBehavior",
-                 static_cast<long>(prepareSupportDefaultBehavior.value()));
+  (*repr_)["prepareSupportDefaultBehavior"] =
+      static_cast<long>(prepareSupportDefaultBehavior.value());
   return *this;
 }
 
@@ -21888,8 +21622,8 @@ auto RenameClientCapabilities::honorsChangeAnnotations(
     repr_->erase("honorsChangeAnnotations");
     return *this;
   }
-  repr_->emplace("honorsChangeAnnotations",
-                 std::move(honorsChangeAnnotations.value()));
+  (*repr_)["honorsChangeAnnotations"] =
+      std::move(honorsChangeAnnotations.value());
   return *this;
 }
 
@@ -21904,6 +21638,7 @@ auto FoldingRangeClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21913,6 +21648,7 @@ auto FoldingRangeClientCapabilities::rangeLimit() const -> std::optional<long> {
 
   auto& value = (*repr_)["rangeLimit"];
 
+  if (value.is_null()) value = 0;
   assert(value.is_number_integer());
   return value.get<long>();
 }
@@ -21923,6 +21659,7 @@ auto FoldingRangeClientCapabilities::lineFoldingOnly() const
 
   auto& value = (*repr_)["lineFoldingOnly"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -21952,7 +21689,7 @@ auto FoldingRangeClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -21962,7 +21699,7 @@ auto FoldingRangeClientCapabilities::rangeLimit(std::optional<long> rangeLimit)
     repr_->erase("rangeLimit");
     return *this;
   }
-  repr_->emplace("rangeLimit", std::move(rangeLimit.value()));
+  (*repr_)["rangeLimit"] = std::move(rangeLimit.value());
   return *this;
 }
 
@@ -21972,7 +21709,7 @@ auto FoldingRangeClientCapabilities::lineFoldingOnly(
     repr_->erase("lineFoldingOnly");
     return *this;
   }
-  repr_->emplace("lineFoldingOnly", std::move(lineFoldingOnly.value()));
+  (*repr_)["lineFoldingOnly"] = std::move(lineFoldingOnly.value());
   return *this;
 }
 
@@ -21983,7 +21720,7 @@ auto FoldingRangeClientCapabilities::foldingRangeKind(
     repr_->erase("foldingRangeKind");
     return *this;
   }
-  repr_->emplace("foldingRangeKind", foldingRangeKind.value());
+  (*repr_)["foldingRangeKind"] = foldingRangeKind.value();
   return *this;
 }
 
@@ -21994,7 +21731,7 @@ auto FoldingRangeClientCapabilities::foldingRange(
     repr_->erase("foldingRange");
     return *this;
   }
-  repr_->emplace("foldingRange", foldingRange.value());
+  (*repr_)["foldingRange"] = foldingRange.value();
   return *this;
 }
 
@@ -22009,6 +21746,7 @@ auto SelectionRangeClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22020,7 +21758,7 @@ auto SelectionRangeClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22035,6 +21773,7 @@ auto PublishDiagnosticsClientCapabilities::versionSupport() const
 
   auto& value = (*repr_)["versionSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22045,6 +21784,7 @@ auto PublishDiagnosticsClientCapabilities::relatedInformation() const
 
   auto& value = (*repr_)["relatedInformation"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22064,6 +21804,7 @@ auto PublishDiagnosticsClientCapabilities::codeDescriptionSupport() const
 
   auto& value = (*repr_)["codeDescriptionSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22074,6 +21815,7 @@ auto PublishDiagnosticsClientCapabilities::dataSupport() const
 
   auto& value = (*repr_)["dataSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22085,7 +21827,7 @@ auto PublishDiagnosticsClientCapabilities::versionSupport(
     repr_->erase("versionSupport");
     return *this;
   }
-  repr_->emplace("versionSupport", std::move(versionSupport.value()));
+  (*repr_)["versionSupport"] = std::move(versionSupport.value());
   return *this;
 }
 
@@ -22096,7 +21838,7 @@ auto PublishDiagnosticsClientCapabilities::relatedInformation(
     repr_->erase("relatedInformation");
     return *this;
   }
-  repr_->emplace("relatedInformation", std::move(relatedInformation.value()));
+  (*repr_)["relatedInformation"] = std::move(relatedInformation.value());
   return *this;
 }
 
@@ -22107,7 +21849,7 @@ auto PublishDiagnosticsClientCapabilities::tagSupport(
     repr_->erase("tagSupport");
     return *this;
   }
-  repr_->emplace("tagSupport", tagSupport.value());
+  (*repr_)["tagSupport"] = tagSupport.value();
   return *this;
 }
 
@@ -22118,8 +21860,8 @@ auto PublishDiagnosticsClientCapabilities::codeDescriptionSupport(
     repr_->erase("codeDescriptionSupport");
     return *this;
   }
-  repr_->emplace("codeDescriptionSupport",
-                 std::move(codeDescriptionSupport.value()));
+  (*repr_)["codeDescriptionSupport"] =
+      std::move(codeDescriptionSupport.value());
   return *this;
 }
 
@@ -22129,7 +21871,7 @@ auto PublishDiagnosticsClientCapabilities::dataSupport(
     repr_->erase("dataSupport");
     return *this;
   }
-  repr_->emplace("dataSupport", std::move(dataSupport.value()));
+  (*repr_)["dataSupport"] = std::move(dataSupport.value());
   return *this;
 }
 
@@ -22144,6 +21886,7 @@ auto CallHierarchyClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22155,7 +21898,7 @@ auto CallHierarchyClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22174,6 +21917,7 @@ auto SemanticTokensClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22189,7 +21933,7 @@ auto SemanticTokensClientCapabilities::tokenTypes() const
     -> Vector<std::string> {
   auto& value = (*repr_)["tokenTypes"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -22197,14 +21941,14 @@ auto SemanticTokensClientCapabilities::tokenModifiers() const
     -> Vector<std::string> {
   auto& value = (*repr_)["tokenModifiers"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
 auto SemanticTokensClientCapabilities::formats() const -> Vector<TokenFormat> {
   auto& value = (*repr_)["formats"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<TokenFormat>(value);
 }
 
@@ -22214,6 +21958,7 @@ auto SemanticTokensClientCapabilities::overlappingTokenSupport() const
 
   auto& value = (*repr_)["overlappingTokenSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22224,6 +21969,7 @@ auto SemanticTokensClientCapabilities::multilineTokenSupport() const
 
   auto& value = (*repr_)["multilineTokenSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22234,6 +21980,7 @@ auto SemanticTokensClientCapabilities::serverCancelSupport() const
 
   auto& value = (*repr_)["serverCancelSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22244,6 +21991,7 @@ auto SemanticTokensClientCapabilities::augmentsSyntaxTokens() const
 
   auto& value = (*repr_)["augmentsSyntaxTokens"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22255,14 +22003,14 @@ auto SemanticTokensClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
 auto SemanticTokensClientCapabilities::requests(
     ClientSemanticTokensRequestOptions requests)
     -> SemanticTokensClientCapabilities& {
-  repr_->emplace("requests", requests);
+  (*repr_)["requests"] = requests;
   return *this;
 }
 
@@ -22294,8 +22042,8 @@ auto SemanticTokensClientCapabilities::overlappingTokenSupport(
     repr_->erase("overlappingTokenSupport");
     return *this;
   }
-  repr_->emplace("overlappingTokenSupport",
-                 std::move(overlappingTokenSupport.value()));
+  (*repr_)["overlappingTokenSupport"] =
+      std::move(overlappingTokenSupport.value());
   return *this;
 }
 
@@ -22306,8 +22054,7 @@ auto SemanticTokensClientCapabilities::multilineTokenSupport(
     repr_->erase("multilineTokenSupport");
     return *this;
   }
-  repr_->emplace("multilineTokenSupport",
-                 std::move(multilineTokenSupport.value()));
+  (*repr_)["multilineTokenSupport"] = std::move(multilineTokenSupport.value());
   return *this;
 }
 
@@ -22318,7 +22065,7 @@ auto SemanticTokensClientCapabilities::serverCancelSupport(
     repr_->erase("serverCancelSupport");
     return *this;
   }
-  repr_->emplace("serverCancelSupport", std::move(serverCancelSupport.value()));
+  (*repr_)["serverCancelSupport"] = std::move(serverCancelSupport.value());
   return *this;
 }
 
@@ -22329,8 +22076,7 @@ auto SemanticTokensClientCapabilities::augmentsSyntaxTokens(
     repr_->erase("augmentsSyntaxTokens");
     return *this;
   }
-  repr_->emplace("augmentsSyntaxTokens",
-                 std::move(augmentsSyntaxTokens.value()));
+  (*repr_)["augmentsSyntaxTokens"] = std::move(augmentsSyntaxTokens.value());
   return *this;
 }
 
@@ -22345,6 +22091,7 @@ auto LinkedEditingRangeClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22356,7 +22103,7 @@ auto LinkedEditingRangeClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22371,6 +22118,7 @@ auto MonikerClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22381,7 +22129,7 @@ auto MonikerClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22396,6 +22144,7 @@ auto TypeHierarchyClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22407,7 +22156,7 @@ auto TypeHierarchyClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22422,6 +22171,7 @@ auto InlineValueClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22432,7 +22182,7 @@ auto InlineValueClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22447,6 +22197,7 @@ auto InlayHintClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22466,7 +22217,7 @@ auto InlayHintClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22477,7 +22228,7 @@ auto InlayHintClientCapabilities::resolveSupport(
     repr_->erase("resolveSupport");
     return *this;
   }
-  repr_->emplace("resolveSupport", resolveSupport.value());
+  (*repr_)["resolveSupport"] = resolveSupport.value();
   return *this;
 }
 
@@ -22492,6 +22243,7 @@ auto DiagnosticClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22502,6 +22254,7 @@ auto DiagnosticClientCapabilities::relatedDocumentSupport() const
 
   auto& value = (*repr_)["relatedDocumentSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22512,6 +22265,7 @@ auto DiagnosticClientCapabilities::relatedInformation() const
 
   auto& value = (*repr_)["relatedInformation"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22531,6 +22285,7 @@ auto DiagnosticClientCapabilities::codeDescriptionSupport() const
 
   auto& value = (*repr_)["codeDescriptionSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22540,6 +22295,7 @@ auto DiagnosticClientCapabilities::dataSupport() const -> std::optional<bool> {
 
   auto& value = (*repr_)["dataSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22550,7 +22306,7 @@ auto DiagnosticClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22561,8 +22317,8 @@ auto DiagnosticClientCapabilities::relatedDocumentSupport(
     repr_->erase("relatedDocumentSupport");
     return *this;
   }
-  repr_->emplace("relatedDocumentSupport",
-                 std::move(relatedDocumentSupport.value()));
+  (*repr_)["relatedDocumentSupport"] =
+      std::move(relatedDocumentSupport.value());
   return *this;
 }
 
@@ -22572,7 +22328,7 @@ auto DiagnosticClientCapabilities::relatedInformation(
     repr_->erase("relatedInformation");
     return *this;
   }
-  repr_->emplace("relatedInformation", std::move(relatedInformation.value()));
+  (*repr_)["relatedInformation"] = std::move(relatedInformation.value());
   return *this;
 }
 
@@ -22583,7 +22339,7 @@ auto DiagnosticClientCapabilities::tagSupport(
     repr_->erase("tagSupport");
     return *this;
   }
-  repr_->emplace("tagSupport", tagSupport.value());
+  (*repr_)["tagSupport"] = tagSupport.value();
   return *this;
 }
 
@@ -22594,8 +22350,8 @@ auto DiagnosticClientCapabilities::codeDescriptionSupport(
     repr_->erase("codeDescriptionSupport");
     return *this;
   }
-  repr_->emplace("codeDescriptionSupport",
-                 std::move(codeDescriptionSupport.value()));
+  (*repr_)["codeDescriptionSupport"] =
+      std::move(codeDescriptionSupport.value());
   return *this;
 }
 
@@ -22605,7 +22361,7 @@ auto DiagnosticClientCapabilities::dataSupport(std::optional<bool> dataSupport)
     repr_->erase("dataSupport");
     return *this;
   }
-  repr_->emplace("dataSupport", std::move(dataSupport.value()));
+  (*repr_)["dataSupport"] = std::move(dataSupport.value());
   return *this;
 }
 
@@ -22620,6 +22376,7 @@ auto InlineCompletionClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22631,7 +22388,7 @@ auto InlineCompletionClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22646,6 +22403,7 @@ auto NotebookDocumentSyncClientCapabilities::dynamicRegistration() const
 
   auto& value = (*repr_)["dynamicRegistration"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22656,6 +22414,7 @@ auto NotebookDocumentSyncClientCapabilities::executionSummarySupport() const
 
   auto& value = (*repr_)["executionSummarySupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22667,7 +22426,7 @@ auto NotebookDocumentSyncClientCapabilities::dynamicRegistration(
     repr_->erase("dynamicRegistration");
     return *this;
   }
-  repr_->emplace("dynamicRegistration", std::move(dynamicRegistration.value()));
+  (*repr_)["dynamicRegistration"] = std::move(dynamicRegistration.value());
   return *this;
 }
 
@@ -22678,8 +22437,8 @@ auto NotebookDocumentSyncClientCapabilities::executionSummarySupport(
     repr_->erase("executionSummarySupport");
     return *this;
   }
-  repr_->emplace("executionSummarySupport",
-                 std::move(executionSummarySupport.value()));
+  (*repr_)["executionSummarySupport"] =
+      std::move(executionSummarySupport.value());
   return *this;
 }
 
@@ -22704,7 +22463,7 @@ auto ShowMessageRequestClientCapabilities::messageActionItem(
     repr_->erase("messageActionItem");
     return *this;
   }
-  repr_->emplace("messageActionItem", messageActionItem.value());
+  (*repr_)["messageActionItem"] = messageActionItem.value();
   return *this;
 }
 
@@ -22717,13 +22476,14 @@ ShowDocumentClientCapabilities::operator bool() const {
 auto ShowDocumentClientCapabilities::support() const -> bool {
   auto& value = (*repr_)["support"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
 
 auto ShowDocumentClientCapabilities::support(bool support)
     -> ShowDocumentClientCapabilities& {
-  repr_->emplace("support", std::move(support));
+  (*repr_)["support"] = std::move(support);
   return *this;
 }
 
@@ -22737,6 +22497,7 @@ StaleRequestSupportOptions::operator bool() const {
 auto StaleRequestSupportOptions::cancel() const -> bool {
   auto& value = (*repr_)["cancel"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22745,13 +22506,13 @@ auto StaleRequestSupportOptions::retryOnContentModified() const
     -> Vector<std::string> {
   auto& value = (*repr_)["retryOnContentModified"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
 auto StaleRequestSupportOptions::cancel(bool cancel)
     -> StaleRequestSupportOptions& {
-  repr_->emplace("cancel", std::move(cancel));
+  (*repr_)["cancel"] = std::move(cancel);
   return *this;
 }
 
@@ -22772,6 +22533,7 @@ auto RegularExpressionsClientCapabilities::engine() const
     -> RegularExpressionEngineKind {
   auto& value = (*repr_)["engine"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -22782,6 +22544,7 @@ auto RegularExpressionsClientCapabilities::version() const
 
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -22801,7 +22564,7 @@ auto RegularExpressionsClientCapabilities::version(
     repr_->erase("version");
     return *this;
   }
-  repr_->emplace("version", std::move(version.value()));
+  (*repr_)["version"] = std::move(version.value());
   return *this;
 }
 
@@ -22814,6 +22577,7 @@ MarkdownClientCapabilities::operator bool() const {
 auto MarkdownClientCapabilities::parser() const -> std::string {
   auto& value = (*repr_)["parser"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -22823,6 +22587,7 @@ auto MarkdownClientCapabilities::version() const -> std::optional<std::string> {
 
   auto& value = (*repr_)["version"];
 
+  if (value.is_null()) value = "";
   assert(value.is_string());
   return value.get<std::string>();
 }
@@ -22833,13 +22598,13 @@ auto MarkdownClientCapabilities::allowedTags() const
 
   auto& value = (*repr_)["allowedTags"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
 auto MarkdownClientCapabilities::parser(std::string parser)
     -> MarkdownClientCapabilities& {
-  repr_->emplace("parser", std::move(parser));
+  (*repr_)["parser"] = std::move(parser);
   return *this;
 }
 
@@ -22849,7 +22614,7 @@ auto MarkdownClientCapabilities::version(std::optional<std::string> version)
     repr_->erase("version");
     return *this;
   }
-  repr_->emplace("version", std::move(version.value()));
+  (*repr_)["version"] = std::move(version.value());
   return *this;
 }
 
@@ -22876,6 +22641,7 @@ auto ChangeAnnotationsSupportOptions::groupsOnLabel() const
 
   auto& value = (*repr_)["groupsOnLabel"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22886,7 +22652,7 @@ auto ChangeAnnotationsSupportOptions::groupsOnLabel(
     repr_->erase("groupsOnLabel");
     return *this;
   }
-  repr_->emplace("groupsOnLabel", std::move(groupsOnLabel.value()));
+  (*repr_)["groupsOnLabel"] = std::move(groupsOnLabel.value());
   return *this;
 }
 
@@ -22901,7 +22667,7 @@ auto ClientSymbolKindOptions::valueSet() const
 
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SymbolKind>(value);
 }
 
@@ -22924,7 +22690,7 @@ ClientSymbolTagOptions::operator bool() const {
 auto ClientSymbolTagOptions::valueSet() const -> Vector<SymbolTag> {
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<SymbolTag>(value);
 }
 
@@ -22943,7 +22709,7 @@ ClientSymbolResolveOptions::operator bool() const {
 auto ClientSymbolResolveOptions::properties() const -> Vector<std::string> {
   auto& value = (*repr_)["properties"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -22965,6 +22731,7 @@ auto ClientCompletionItemOptions::snippetSupport() const
 
   auto& value = (*repr_)["snippetSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22975,6 +22742,7 @@ auto ClientCompletionItemOptions::commitCharactersSupport() const
 
   auto& value = (*repr_)["commitCharactersSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -22985,7 +22753,7 @@ auto ClientCompletionItemOptions::documentationFormat() const
 
   auto& value = (*repr_)["documentationFormat"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<MarkupKind>(value);
 }
 
@@ -22995,6 +22763,7 @@ auto ClientCompletionItemOptions::deprecatedSupport() const
 
   auto& value = (*repr_)["deprecatedSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23005,6 +22774,7 @@ auto ClientCompletionItemOptions::preselectSupport() const
 
   auto& value = (*repr_)["preselectSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23024,6 +22794,7 @@ auto ClientCompletionItemOptions::insertReplaceSupport() const
 
   auto& value = (*repr_)["insertReplaceSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23052,6 +22823,7 @@ auto ClientCompletionItemOptions::labelDetailsSupport() const
 
   auto& value = (*repr_)["labelDetailsSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23062,7 +22834,7 @@ auto ClientCompletionItemOptions::snippetSupport(
     repr_->erase("snippetSupport");
     return *this;
   }
-  repr_->emplace("snippetSupport", std::move(snippetSupport.value()));
+  (*repr_)["snippetSupport"] = std::move(snippetSupport.value());
   return *this;
 }
 
@@ -23073,8 +22845,8 @@ auto ClientCompletionItemOptions::commitCharactersSupport(
     repr_->erase("commitCharactersSupport");
     return *this;
   }
-  repr_->emplace("commitCharactersSupport",
-                 std::move(commitCharactersSupport.value()));
+  (*repr_)["commitCharactersSupport"] =
+      std::move(commitCharactersSupport.value());
   return *this;
 }
 
@@ -23096,7 +22868,7 @@ auto ClientCompletionItemOptions::deprecatedSupport(
     repr_->erase("deprecatedSupport");
     return *this;
   }
-  repr_->emplace("deprecatedSupport", std::move(deprecatedSupport.value()));
+  (*repr_)["deprecatedSupport"] = std::move(deprecatedSupport.value());
   return *this;
 }
 
@@ -23106,7 +22878,7 @@ auto ClientCompletionItemOptions::preselectSupport(
     repr_->erase("preselectSupport");
     return *this;
   }
-  repr_->emplace("preselectSupport", std::move(preselectSupport.value()));
+  (*repr_)["preselectSupport"] = std::move(preselectSupport.value());
   return *this;
 }
 
@@ -23117,7 +22889,7 @@ auto ClientCompletionItemOptions::tagSupport(
     repr_->erase("tagSupport");
     return *this;
   }
-  repr_->emplace("tagSupport", tagSupport.value());
+  (*repr_)["tagSupport"] = tagSupport.value();
   return *this;
 }
 
@@ -23127,8 +22899,7 @@ auto ClientCompletionItemOptions::insertReplaceSupport(
     repr_->erase("insertReplaceSupport");
     return *this;
   }
-  repr_->emplace("insertReplaceSupport",
-                 std::move(insertReplaceSupport.value()));
+  (*repr_)["insertReplaceSupport"] = std::move(insertReplaceSupport.value());
   return *this;
 }
 
@@ -23139,7 +22910,7 @@ auto ClientCompletionItemOptions::resolveSupport(
     repr_->erase("resolveSupport");
     return *this;
   }
-  repr_->emplace("resolveSupport", resolveSupport.value());
+  (*repr_)["resolveSupport"] = resolveSupport.value();
   return *this;
 }
 
@@ -23150,7 +22921,7 @@ auto ClientCompletionItemOptions::insertTextModeSupport(
     repr_->erase("insertTextModeSupport");
     return *this;
   }
-  repr_->emplace("insertTextModeSupport", insertTextModeSupport.value());
+  (*repr_)["insertTextModeSupport"] = insertTextModeSupport.value();
   return *this;
 }
 
@@ -23160,7 +22931,7 @@ auto ClientCompletionItemOptions::labelDetailsSupport(
     repr_->erase("labelDetailsSupport");
     return *this;
   }
-  repr_->emplace("labelDetailsSupport", std::move(labelDetailsSupport.value()));
+  (*repr_)["labelDetailsSupport"] = std::move(labelDetailsSupport.value());
   return *this;
 }
 
@@ -23175,7 +22946,7 @@ auto ClientCompletionItemOptionsKind::valueSet() const
 
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CompletionItemKind>(value);
 }
 
@@ -23202,7 +22973,7 @@ auto CompletionListCapabilities::itemDefaults() const
 
   auto& value = (*repr_)["itemDefaults"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -23212,6 +22983,7 @@ auto CompletionListCapabilities::applyKindSupport() const
 
   auto& value = (*repr_)["applyKindSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23234,7 +23006,7 @@ auto CompletionListCapabilities::applyKindSupport(
     repr_->erase("applyKindSupport");
     return *this;
   }
-  repr_->emplace("applyKindSupport", std::move(applyKindSupport.value()));
+  (*repr_)["applyKindSupport"] = std::move(applyKindSupport.value());
   return *this;
 }
 
@@ -23249,7 +23021,7 @@ auto ClientSignatureInformationOptions::documentationFormat() const
 
   auto& value = (*repr_)["documentationFormat"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<MarkupKind>(value);
 }
 
@@ -23268,6 +23040,7 @@ auto ClientSignatureInformationOptions::activeParameterSupport() const
 
   auto& value = (*repr_)["activeParameterSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23278,6 +23051,7 @@ auto ClientSignatureInformationOptions::noActiveParameterSupport() const
 
   auto& value = (*repr_)["noActiveParameterSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23302,7 +23076,7 @@ auto ClientSignatureInformationOptions::parameterInformation(
     repr_->erase("parameterInformation");
     return *this;
   }
-  repr_->emplace("parameterInformation", parameterInformation.value());
+  (*repr_)["parameterInformation"] = parameterInformation.value();
   return *this;
 }
 
@@ -23313,8 +23087,8 @@ auto ClientSignatureInformationOptions::activeParameterSupport(
     repr_->erase("activeParameterSupport");
     return *this;
   }
-  repr_->emplace("activeParameterSupport",
-                 std::move(activeParameterSupport.value()));
+  (*repr_)["activeParameterSupport"] =
+      std::move(activeParameterSupport.value());
   return *this;
 }
 
@@ -23325,8 +23099,8 @@ auto ClientSignatureInformationOptions::noActiveParameterSupport(
     repr_->erase("noActiveParameterSupport");
     return *this;
   }
-  repr_->emplace("noActiveParameterSupport",
-                 std::move(noActiveParameterSupport.value()));
+  (*repr_)["noActiveParameterSupport"] =
+      std::move(noActiveParameterSupport.value());
   return *this;
 }
 
@@ -23346,7 +23120,7 @@ auto ClientCodeActionLiteralOptions::codeActionKind() const
 auto ClientCodeActionLiteralOptions::codeActionKind(
     ClientCodeActionKindOptions codeActionKind)
     -> ClientCodeActionLiteralOptions& {
-  repr_->emplace("codeActionKind", codeActionKind);
+  (*repr_)["codeActionKind"] = codeActionKind;
   return *this;
 }
 
@@ -23359,7 +23133,7 @@ ClientCodeActionResolveOptions::operator bool() const {
 auto ClientCodeActionResolveOptions::properties() const -> Vector<std::string> {
   auto& value = (*repr_)["properties"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -23379,7 +23153,7 @@ CodeActionTagOptions::operator bool() const {
 auto CodeActionTagOptions::valueSet() const -> Vector<CodeActionTag> {
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CodeActionTag>(value);
 }
 
@@ -23398,7 +23172,7 @@ ClientCodeLensResolveOptions::operator bool() const {
 auto ClientCodeLensResolveOptions::properties() const -> Vector<std::string> {
   auto& value = (*repr_)["properties"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -23420,7 +23194,7 @@ auto ClientFoldingRangeKindOptions::valueSet() const
 
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<FoldingRangeKind>(value);
 }
 
@@ -23446,6 +23220,7 @@ auto ClientFoldingRangeOptions::collapsedText() const -> std::optional<bool> {
 
   auto& value = (*repr_)["collapsedText"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23456,7 +23231,7 @@ auto ClientFoldingRangeOptions::collapsedText(std::optional<bool> collapsedText)
     repr_->erase("collapsedText");
     return *this;
   }
-  repr_->emplace("collapsedText", std::move(collapsedText.value()));
+  (*repr_)["collapsedText"] = std::move(collapsedText.value());
   return *this;
 }
 
@@ -23471,6 +23246,7 @@ auto DiagnosticsCapabilities::relatedInformation() const
 
   auto& value = (*repr_)["relatedInformation"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23490,6 +23266,7 @@ auto DiagnosticsCapabilities::codeDescriptionSupport() const
 
   auto& value = (*repr_)["codeDescriptionSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23499,6 +23276,7 @@ auto DiagnosticsCapabilities::dataSupport() const -> std::optional<bool> {
 
   auto& value = (*repr_)["dataSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23509,7 +23287,7 @@ auto DiagnosticsCapabilities::relatedInformation(
     repr_->erase("relatedInformation");
     return *this;
   }
-  repr_->emplace("relatedInformation", std::move(relatedInformation.value()));
+  (*repr_)["relatedInformation"] = std::move(relatedInformation.value());
   return *this;
 }
 
@@ -23520,7 +23298,7 @@ auto DiagnosticsCapabilities::tagSupport(
     repr_->erase("tagSupport");
     return *this;
   }
-  repr_->emplace("tagSupport", tagSupport.value());
+  (*repr_)["tagSupport"] = tagSupport.value();
   return *this;
 }
 
@@ -23530,8 +23308,8 @@ auto DiagnosticsCapabilities::codeDescriptionSupport(
     repr_->erase("codeDescriptionSupport");
     return *this;
   }
-  repr_->emplace("codeDescriptionSupport",
-                 std::move(codeDescriptionSupport.value()));
+  (*repr_)["codeDescriptionSupport"] =
+      std::move(codeDescriptionSupport.value());
   return *this;
 }
 
@@ -23541,7 +23319,7 @@ auto DiagnosticsCapabilities::dataSupport(std::optional<bool> dataSupport)
     repr_->erase("dataSupport");
     return *this;
   }
-  repr_->emplace("dataSupport", std::move(dataSupport.value()));
+  (*repr_)["dataSupport"] = std::move(dataSupport.value());
   return *this;
 }
 
@@ -23551,26 +23329,25 @@ ClientSemanticTokensRequestOptions::operator bool() const {
 }
 
 auto ClientSemanticTokensRequestOptions::range() const
-    -> std::optional<std::variant<std::monostate, bool, json>> {
+    -> std::optional<std::variant<bool, json>> {
   if (!repr_->contains("range")) return std::nullopt;
 
   auto& value = (*repr_)["range"];
 
-  std::variant<std::monostate, bool, json> result;
+  std::variant<bool, json> result;
 
   details::try_emplace(result, value);
 
   return result;
 }
 
-auto ClientSemanticTokensRequestOptions::full() const -> std::optional<
-    std::variant<std::monostate, bool, ClientSemanticTokensRequestFullDelta>> {
+auto ClientSemanticTokensRequestOptions::full() const
+    -> std::optional<std::variant<bool, ClientSemanticTokensRequestFullDelta>> {
   if (!repr_->contains("full")) return std::nullopt;
 
   auto& value = (*repr_)["full"];
 
-  std::variant<std::monostate, bool, ClientSemanticTokensRequestFullDelta>
-      result;
+  std::variant<bool, ClientSemanticTokensRequestFullDelta> result;
 
   details::try_emplace(result, value);
 
@@ -23578,23 +23355,17 @@ auto ClientSemanticTokensRequestOptions::full() const -> std::optional<
 }
 
 auto ClientSemanticTokensRequestOptions::range(
-    std::optional<std::variant<std::monostate, bool, json>> range)
+    std::optional<std::variant<bool, json>> range)
     -> ClientSemanticTokensRequestOptions& {
   if (!range.has_value()) {
     repr_->erase("range");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(bool range) { repr_->emplace("range", std::move(range)); }
+    void operator()(bool range) { (*repr_)["range"] = std::move(range); }
 
     void operator()(json range) {
       lsp_runtime_error(
@@ -23608,27 +23379,20 @@ auto ClientSemanticTokensRequestOptions::range(
 }
 
 auto ClientSemanticTokensRequestOptions::full(
-    std::optional<std::variant<std::monostate, bool,
-                               ClientSemanticTokensRequestFullDelta>>
+    std::optional<std::variant<bool, ClientSemanticTokensRequestFullDelta>>
         full) -> ClientSemanticTokensRequestOptions& {
   if (!full.has_value()) {
     repr_->erase("full");
     return *this;
   }
 
-  // or type
-
   struct {
     json* repr_;
 
-    void operator()(std::monostate) {
-      lsp_runtime_error("monostate is not a valid a property value");
-    }
-
-    void operator()(bool full) { repr_->emplace("full", std::move(full)); }
+    void operator()(bool full) { (*repr_)["full"] = std::move(full); }
 
     void operator()(ClientSemanticTokensRequestFullDelta full) {
-      repr_->emplace("full", full);
+      (*repr_)["full"] = full;
     }
   } v{repr_};
 
@@ -23646,7 +23410,7 @@ ClientInlayHintResolveOptions::operator bool() const {
 auto ClientInlayHintResolveOptions::properties() const -> Vector<std::string> {
   auto& value = (*repr_)["properties"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -23668,6 +23432,7 @@ auto ClientShowMessageActionItemOptions::additionalPropertiesSupport() const
 
   auto& value = (*repr_)["additionalPropertiesSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23679,8 +23444,8 @@ auto ClientShowMessageActionItemOptions::additionalPropertiesSupport(
     repr_->erase("additionalPropertiesSupport");
     return *this;
   }
-  repr_->emplace("additionalPropertiesSupport",
-                 std::move(additionalPropertiesSupport.value()));
+  (*repr_)["additionalPropertiesSupport"] =
+      std::move(additionalPropertiesSupport.value());
   return *this;
 }
 
@@ -23693,7 +23458,7 @@ CompletionItemTagOptions::operator bool() const {
 auto CompletionItemTagOptions::valueSet() const -> Vector<CompletionItemTag> {
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CompletionItemTag>(value);
 }
 
@@ -23713,7 +23478,7 @@ auto ClientCompletionItemResolveOptions::properties() const
     -> Vector<std::string> {
   auto& value = (*repr_)["properties"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<std::string>(value);
 }
 
@@ -23734,7 +23499,7 @@ auto ClientCompletionItemInsertTextModeOptions::valueSet() const
     -> Vector<InsertTextMode> {
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<InsertTextMode>(value);
 }
 
@@ -23757,6 +23522,7 @@ auto ClientSignatureParameterInformationOptions::labelOffsetSupport() const
 
   auto& value = (*repr_)["labelOffsetSupport"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23768,7 +23534,7 @@ auto ClientSignatureParameterInformationOptions::labelOffsetSupport(
     repr_->erase("labelOffsetSupport");
     return *this;
   }
-  repr_->emplace("labelOffsetSupport", std::move(labelOffsetSupport.value()));
+  (*repr_)["labelOffsetSupport"] = std::move(labelOffsetSupport.value());
   return *this;
 }
 
@@ -23781,7 +23547,7 @@ ClientCodeActionKindOptions::operator bool() const {
 auto ClientCodeActionKindOptions::valueSet() const -> Vector<CodeActionKind> {
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<CodeActionKind>(value);
 }
 
@@ -23800,7 +23566,7 @@ ClientDiagnosticsTagOptions::operator bool() const {
 auto ClientDiagnosticsTagOptions::valueSet() const -> Vector<DiagnosticTag> {
   auto& value = (*repr_)["valueSet"];
 
-  assert(value.is_array());
+  if (value.is_null()) value = json::array();
   return Vector<DiagnosticTag>(value);
 }
 
@@ -23821,6 +23587,7 @@ auto ClientSemanticTokensRequestFullDelta::delta() const
 
   auto& value = (*repr_)["delta"];
 
+  if (value.is_null()) value = false;
   assert(value.is_boolean());
   return value.get<bool>();
 }
@@ -23831,7 +23598,7 @@ auto ClientSemanticTokensRequestFullDelta::delta(std::optional<bool> delta)
     repr_->erase("delta");
     return *this;
   }
-  repr_->emplace("delta", std::move(delta.value()));
+  (*repr_)["delta"] = std::move(delta.value());
   return *this;
 }
 }  // namespace cxx::lsp
diff --git a/src/lsp/cxx/lsp/types.h b/src/lsp/cxx/lsp/types.h
index 2f6e781e..87144c52 100644
--- a/src/lsp/cxx/lsp/types.h
+++ b/src/lsp/cxx/lsp/types.h
@@ -72,15 +72,15 @@ class ImplementationRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> ImplementationRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> ImplementationRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> ImplementationRegistrationOptions&;
@@ -121,15 +121,15 @@ class TypeDefinitionRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> TypeDefinitionRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> TypeDefinitionRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> TypeDefinitionRegistrationOptions&;
@@ -219,15 +219,15 @@ class DocumentColorRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DocumentColorRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DocumentColorRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> DocumentColorRegistrationOptions&;
@@ -305,11 +305,11 @@ class TextDocumentRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> TextDocumentRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> TextDocumentRegistrationOptions&;
 };
 
 class FoldingRangeParams final : public LSPObject {
@@ -371,15 +371,15 @@ class FoldingRangeRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> FoldingRangeRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> FoldingRangeRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> FoldingRangeRegistrationOptions&;
@@ -421,7 +421,7 @@ class DeclarationRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
@@ -429,8 +429,8 @@ class DeclarationRegistrationOptions final : public LSPObject {
       -> DeclarationRegistrationOptions&;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DeclarationRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DeclarationRegistrationOptions&;
 
   auto id(std::optional<std::string> id) -> DeclarationRegistrationOptions&;
 };
@@ -485,7 +485,7 @@ class SelectionRangeRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
@@ -493,8 +493,8 @@ class SelectionRangeRegistrationOptions final : public LSPObject {
       -> SelectionRangeRegistrationOptions&;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> SelectionRangeRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> SelectionRangeRegistrationOptions&;
 
   auto id(std::optional<std::string> id) -> SelectionRangeRegistrationOptions&;
 };
@@ -588,15 +588,15 @@ class CallHierarchyRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> CallHierarchyRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> CallHierarchyRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> CallHierarchyRegistrationOptions&;
@@ -731,33 +731,31 @@ class SemanticTokensRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto legend() const -> SemanticTokensLegend;
 
-  [[nodiscard]] auto range() const
-      -> std::optional<std::variant<std::monostate, bool, json>>;
+  [[nodiscard]] auto range() const -> std::optional<std::variant<bool, json>>;
 
-  [[nodiscard]] auto full() const -> std::optional<
-      std::variant<std::monostate, bool, SemanticTokensFullDelta>>;
+  [[nodiscard]] auto full() const
+      -> std::optional<std::variant<bool, SemanticTokensFullDelta>>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> SemanticTokensRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> SemanticTokensRegistrationOptions&;
 
   auto legend(SemanticTokensLegend legend)
       -> SemanticTokensRegistrationOptions&;
 
-  auto range(std::optional<std::variant<std::monostate, bool, json>> range)
+  auto range(std::optional<std::variant<bool, json>> range)
       -> SemanticTokensRegistrationOptions&;
 
-  auto full(
-      std::optional<std::variant<std::monostate, bool, SemanticTokensFullDelta>>
-          full) -> SemanticTokensRegistrationOptions&;
+  auto full(std::optional<std::variant<bool, SemanticTokensFullDelta>> full)
+      -> SemanticTokensRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> SemanticTokensRegistrationOptions&;
@@ -923,15 +921,15 @@ class LinkedEditingRangeRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> LinkedEditingRangeRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> LinkedEditingRangeRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> LinkedEditingRangeRegistrationOptions&;
@@ -960,9 +958,8 @@ class WorkspaceEdit final : public LSPObject {
   [[nodiscard]] auto changes() const
       -> std::optional<Map<std::string, Vector<TextEdit>>>;
 
-  [[nodiscard]] auto
-  documentChanges() const -> std::optional<Vector<std::variant<
-      std::monostate, TextDocumentEdit, CreateFile, RenameFile, DeleteFile>>>;
+  [[nodiscard]] auto documentChanges() const -> std::optional<Vector<
+      std::variant<TextDocumentEdit, CreateFile, RenameFile, DeleteFile>>>;
 
   [[nodiscard]] auto changeAnnotations() const
       -> std::optional<Map<ChangeAnnotationIdentifier, ChangeAnnotation>>;
@@ -971,8 +968,8 @@ class WorkspaceEdit final : public LSPObject {
       -> WorkspaceEdit&;
 
   auto documentChanges(
-      std::optional<Vector<std::variant<std::monostate, TextDocumentEdit,
-                                        CreateFile, RenameFile, DeleteFile>>>
+      std::optional<Vector<
+          std::variant<TextDocumentEdit, CreateFile, RenameFile, DeleteFile>>>
           documentChanges) -> WorkspaceEdit&;
 
   auto changeAnnotations(
@@ -1069,13 +1066,13 @@ class MonikerRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> MonikerRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> MonikerRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> MonikerRegistrationOptions&;
@@ -1148,15 +1145,15 @@ class TypeHierarchyRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> TypeHierarchyRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> TypeHierarchyRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> TypeHierarchyRegistrationOptions&;
@@ -1239,7 +1236,7 @@ class InlineValueRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
@@ -1247,8 +1244,8 @@ class InlineValueRegistrationOptions final : public LSPObject {
       -> InlineValueRegistrationOptions&;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> InlineValueRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> InlineValueRegistrationOptions&;
 
   auto id(std::optional<std::string> id) -> InlineValueRegistrationOptions&;
 };
@@ -1282,14 +1279,14 @@ class InlayHint final : public LSPObject {
   [[nodiscard]] auto position() const -> Position;
 
   [[nodiscard]] auto label() const
-      -> std::variant<std::monostate, std::string, Vector<InlayHintLabelPart>>;
+      -> std::variant<std::string, Vector<InlayHintLabelPart>>;
 
   [[nodiscard]] auto kind() const -> std::optional<InlayHintKind>;
 
   [[nodiscard]] auto textEdits() const -> std::optional<Vector<TextEdit>>;
 
-  [[nodiscard]] auto tooltip() const -> std::optional<
-      std::variant<std::monostate, std::string, MarkupContent>>;
+  [[nodiscard]] auto tooltip() const
+      -> std::optional<std::variant<std::string, MarkupContent>>;
 
   [[nodiscard]] auto paddingLeft() const -> std::optional<bool>;
 
@@ -1299,17 +1296,15 @@ class InlayHint final : public LSPObject {
 
   auto position(Position position) -> InlayHint&;
 
-  auto label(
-      std::variant<std::monostate, std::string, Vector<InlayHintLabelPart>>
-          label) -> InlayHint&;
+  auto label(std::variant<std::string, Vector<InlayHintLabelPart>> label)
+      -> InlayHint&;
 
   auto kind(std::optional<InlayHintKind> kind) -> InlayHint&;
 
   auto textEdits(std::optional<Vector<TextEdit>> textEdits) -> InlayHint&;
 
-  auto tooltip(
-      std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-          tooltip) -> InlayHint&;
+  auto tooltip(std::optional<std::variant<std::string, MarkupContent>> tooltip)
+      -> InlayHint&;
 
   auto paddingLeft(std::optional<bool> paddingLeft) -> InlayHint&;
 
@@ -1329,7 +1324,7 @@ class InlayHintRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
@@ -1340,8 +1335,8 @@ class InlayHintRegistrationOptions final : public LSPObject {
       -> InlayHintRegistrationOptions&;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> InlayHintRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> InlayHintRegistrationOptions&;
 
   auto id(std::optional<std::string> id) -> InlayHintRegistrationOptions&;
 };
@@ -1385,14 +1380,12 @@ class DocumentDiagnosticReportPartialResult final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto relatedDocuments() const
-      -> Map<std::string,
-             std::variant<std::monostate, FullDocumentDiagnosticReport,
-                          UnchangedDocumentDiagnosticReport>>;
+      -> Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                       UnchangedDocumentDiagnosticReport>>;
 
   auto relatedDocuments(
-      Map<std::string,
-          std::variant<std::monostate, FullDocumentDiagnosticReport,
-                       UnchangedDocumentDiagnosticReport>>
+      Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                    UnchangedDocumentDiagnosticReport>>
           relatedDocuments) -> DocumentDiagnosticReportPartialResult&;
 };
 
@@ -1415,7 +1408,7 @@ class DiagnosticRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto identifier() const -> std::optional<std::string>;
 
@@ -1428,8 +1421,8 @@ class DiagnosticRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DiagnosticRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DiagnosticRegistrationOptions&;
 
   auto identifier(std::optional<std::string> identifier)
       -> DiagnosticRegistrationOptions&;
@@ -1521,17 +1514,17 @@ class NotebookDocumentSyncRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto notebookSelector() const
-      -> Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
+      -> Vector<std::variant<NotebookDocumentFilterWithNotebook,
                              NotebookDocumentFilterWithCells>>;
 
   [[nodiscard]] auto save() const -> std::optional<bool>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
-  auto notebookSelector(
-      Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
-                          NotebookDocumentFilterWithCells>>
-          notebookSelector) -> NotebookDocumentSyncRegistrationOptions&;
+  auto notebookSelector(Vector<std::variant<NotebookDocumentFilterWithNotebook,
+                                            NotebookDocumentFilterWithCells>>
+                            notebookSelector)
+      -> NotebookDocumentSyncRegistrationOptions&;
 
   auto save(std::optional<bool> save)
       -> NotebookDocumentSyncRegistrationOptions&;
@@ -1631,7 +1624,7 @@ class InlineCompletionItem final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto insertText() const
-      -> std::variant<std::monostate, std::string, StringValue>;
+      -> std::variant<std::string, StringValue>;
 
   [[nodiscard]] auto filterText() const -> std::optional<std::string>;
 
@@ -1639,8 +1632,7 @@ class InlineCompletionItem final : public LSPObject {
 
   [[nodiscard]] auto command() const -> std::optional<Command>;
 
-  auto insertText(
-      std::variant<std::monostate, std::string, StringValue> insertText)
+  auto insertText(std::variant<std::string, StringValue> insertText)
       -> InlineCompletionItem&;
 
   auto filterText(std::optional<std::string> filterText)
@@ -1660,7 +1652,7 @@ class InlineCompletionRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto id() const -> std::optional<std::string>;
 
@@ -1668,8 +1660,8 @@ class InlineCompletionRegistrationOptions final : public LSPObject {
       -> InlineCompletionRegistrationOptions&;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> InlineCompletionRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> InlineCompletionRegistrationOptions&;
 
   auto id(std::optional<std::string> id)
       -> InlineCompletionRegistrationOptions&;
@@ -1754,18 +1746,17 @@ class InitializeParams final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto processId() const
-      -> std::variant<std::monostate, int, std::nullptr_t>;
+  [[nodiscard]] auto processId() const -> std::variant<int, std::nullptr_t>;
 
   [[nodiscard]] auto clientInfo() const -> std::optional<ClientInfo>;
 
   [[nodiscard]] auto locale() const -> std::optional<std::string>;
 
-  [[nodiscard]] auto rootPath() const -> std::optional<
-      std::variant<std::monostate, std::string, std::nullptr_t>>;
+  [[nodiscard]] auto rootPath() const
+      -> std::optional<std::variant<std::string, std::nullptr_t>>;
 
   [[nodiscard]] auto rootUri() const
-      -> std::variant<std::monostate, std::string, std::nullptr_t>;
+      -> std::variant<std::string, std::nullptr_t>;
 
   [[nodiscard]] auto capabilities() const -> ClientCapabilities;
 
@@ -1775,10 +1766,10 @@ class InitializeParams final : public LSPObject {
 
   [[nodiscard]] auto workDoneToken() const -> std::optional<ProgressToken>;
 
-  [[nodiscard]] auto workspaceFolders() const -> std::optional<
-      std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t>>;
+  [[nodiscard]] auto workspaceFolders() const
+      -> std::optional<std::variant<Vector<WorkspaceFolder>, std::nullptr_t>>;
 
-  auto processId(std::variant<std::monostate, int, std::nullptr_t> processId)
+  auto processId(std::variant<int, std::nullptr_t> processId)
       -> InitializeParams&;
 
   auto clientInfo(std::optional<ClientInfo> clientInfo) -> InitializeParams&;
@@ -1786,11 +1777,10 @@ class InitializeParams final : public LSPObject {
   auto locale(std::optional<std::string> locale) -> InitializeParams&;
 
   auto rootPath(
-      std::optional<std::variant<std::monostate, std::string, std::nullptr_t>>
-          rootPath) -> InitializeParams&;
+      std::optional<std::variant<std::string, std::nullptr_t>> rootPath)
+      -> InitializeParams&;
 
-  auto rootUri(
-      std::variant<std::monostate, std::string, std::nullptr_t> rootUri)
+  auto rootUri(std::variant<std::string, std::nullptr_t> rootUri)
       -> InitializeParams&;
 
   auto capabilities(ClientCapabilities capabilities) -> InitializeParams&;
@@ -1804,8 +1794,7 @@ class InitializeParams final : public LSPObject {
       -> InitializeParams&;
 
   auto workspaceFolders(
-      std::optional<
-          std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t>>
+      std::optional<std::variant<Vector<WorkspaceFolder>, std::nullptr_t>>
           workspaceFolders) -> InitializeParams&;
 };
 
@@ -1859,12 +1848,12 @@ class DidChangeConfigurationRegistrationOptions final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto section() const -> std::optional<
-      std::variant<std::monostate, std::string, Vector<std::string>>>;
+  [[nodiscard]] auto section() const
+      -> std::optional<std::variant<std::string, Vector<std::string>>>;
 
-  auto section(std::optional<
-               std::variant<std::monostate, std::string, Vector<std::string>>>
-                   section) -> DidChangeConfigurationRegistrationOptions&;
+  auto section(
+      std::optional<std::variant<std::string, Vector<std::string>>> section)
+      -> DidChangeConfigurationRegistrationOptions&;
 };
 
 class ShowMessageParams final : public LSPObject {
@@ -1968,14 +1957,14 @@ class TextDocumentChangeRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto syncKind() const -> TextDocumentSyncKind;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   auto syncKind(TextDocumentSyncKind syncKind)
       -> TextDocumentChangeRegistrationOptions&;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> TextDocumentChangeRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> TextDocumentChangeRegistrationOptions&;
 };
 
 class DidCloseTextDocumentParams final : public LSPObject {
@@ -2013,13 +2002,13 @@ class TextDocumentSaveRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto includeText() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> TextDocumentSaveRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> TextDocumentSaveRegistrationOptions&;
 
   auto includeText(std::optional<bool> includeText)
       -> TextDocumentSaveRegistrationOptions&;
@@ -2144,8 +2133,8 @@ class CompletionItem final : public LSPObject {
 
   [[nodiscard]] auto detail() const -> std::optional<std::string>;
 
-  [[nodiscard]] auto documentation() const -> std::optional<
-      std::variant<std::monostate, std::string, MarkupContent>>;
+  [[nodiscard]] auto documentation() const
+      -> std::optional<std::variant<std::string, MarkupContent>>;
 
   [[nodiscard]] auto deprecated() const -> std::optional<bool>;
 
@@ -2162,8 +2151,8 @@ class CompletionItem final : public LSPObject {
 
   [[nodiscard]] auto insertTextMode() const -> std::optional<InsertTextMode>;
 
-  [[nodiscard]] auto textEdit() const -> std::optional<
-      std::variant<std::monostate, TextEdit, InsertReplaceEdit>>;
+  [[nodiscard]] auto textEdit() const
+      -> std::optional<std::variant<TextEdit, InsertReplaceEdit>>;
 
   [[nodiscard]] auto textEditText() const -> std::optional<std::string>;
 
@@ -2189,8 +2178,8 @@ class CompletionItem final : public LSPObject {
   auto detail(std::optional<std::string> detail) -> CompletionItem&;
 
   auto documentation(
-      std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-          documentation) -> CompletionItem&;
+      std::optional<std::variant<std::string, MarkupContent>> documentation)
+      -> CompletionItem&;
 
   auto deprecated(std::optional<bool> deprecated) -> CompletionItem&;
 
@@ -2209,8 +2198,8 @@ class CompletionItem final : public LSPObject {
       -> CompletionItem&;
 
   auto textEdit(
-      std::optional<std::variant<std::monostate, TextEdit, InsertReplaceEdit>>
-          textEdit) -> CompletionItem&;
+      std::optional<std::variant<TextEdit, InsertReplaceEdit>> textEdit)
+      -> CompletionItem&;
 
   auto textEditText(std::optional<std::string> textEditText) -> CompletionItem&;
 
@@ -2259,7 +2248,7 @@ class CompletionRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto triggerCharacters() const
       -> std::optional<Vector<std::string>>;
@@ -2275,8 +2264,8 @@ class CompletionRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> CompletionRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> CompletionRegistrationOptions&;
 
   auto triggerCharacters(std::optional<Vector<std::string>> triggerCharacters)
       -> CompletionRegistrationOptions&;
@@ -2322,14 +2311,13 @@ class Hover final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto contents() const
-      -> std::variant<std::monostate, MarkupContent, MarkedString,
-                      Vector<MarkedString>>;
+      -> std::variant<MarkupContent, MarkedString, Vector<MarkedString>>;
 
   [[nodiscard]] auto range() const -> std::optional<Range>;
 
-  auto contents(std::variant<std::monostate, MarkupContent, MarkedString,
-                             Vector<MarkedString>>
-                    contents) -> Hover&;
+  auto contents(
+      std::variant<MarkupContent, MarkedString, Vector<MarkedString>> contents)
+      -> Hover&;
 
   auto range(std::optional<Range> range) -> Hover&;
 };
@@ -2341,13 +2329,13 @@ class HoverRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> HoverRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> HoverRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> HoverRegistrationOptions&;
@@ -2390,15 +2378,15 @@ class SignatureHelp final : public LSPObject {
   [[nodiscard]] auto activeSignature() const -> std::optional<long>;
 
   [[nodiscard]] auto activeParameter() const
-      -> std::optional<std::variant<std::monostate, long, std::nullptr_t>>;
+      -> std::optional<std::variant<long, std::nullptr_t>>;
 
   auto signatures(Vector<SignatureInformation> signatures) -> SignatureHelp&;
 
   auto activeSignature(std::optional<long> activeSignature) -> SignatureHelp&;
 
   auto activeParameter(
-      std::optional<std::variant<std::monostate, long, std::nullptr_t>>
-          activeParameter) -> SignatureHelp&;
+      std::optional<std::variant<long, std::nullptr_t>> activeParameter)
+      -> SignatureHelp&;
 };
 
 class SignatureHelpRegistrationOptions final : public LSPObject {
@@ -2408,7 +2396,7 @@ class SignatureHelpRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto triggerCharacters() const
       -> std::optional<Vector<std::string>>;
@@ -2419,8 +2407,8 @@ class SignatureHelpRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> SignatureHelpRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> SignatureHelpRegistrationOptions&;
 
   auto triggerCharacters(std::optional<Vector<std::string>> triggerCharacters)
       -> SignatureHelpRegistrationOptions&;
@@ -2465,13 +2453,13 @@ class DefinitionRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DefinitionRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DefinitionRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> DefinitionRegistrationOptions&;
@@ -2513,13 +2501,13 @@ class ReferenceRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> ReferenceRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> ReferenceRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> ReferenceRegistrationOptions&;
@@ -2573,13 +2561,13 @@ class DocumentHighlightRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DocumentHighlightRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DocumentHighlightRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> DocumentHighlightRegistrationOptions&;
@@ -2686,15 +2674,15 @@ class DocumentSymbolRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto label() const -> std::optional<std::string>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DocumentSymbolRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DocumentSymbolRegistrationOptions&;
 
   auto label(std::optional<std::string> label)
       -> DocumentSymbolRegistrationOptions&;
@@ -2806,7 +2794,7 @@ class CodeActionRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto codeActionKinds() const
       -> std::optional<Vector<CodeActionKind>>;
@@ -2819,8 +2807,8 @@ class CodeActionRegistrationOptions final : public LSPObject {
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> CodeActionRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> CodeActionRegistrationOptions&;
 
   auto codeActionKinds(std::optional<Vector<CodeActionKind>> codeActionKinds)
       -> CodeActionRegistrationOptions&;
@@ -2864,7 +2852,7 @@ class WorkspaceSymbol final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto location() const
-      -> std::variant<std::monostate, Location, LocationUriOnly>;
+      -> std::variant<Location, LocationUriOnly>;
 
   [[nodiscard]] auto data() const -> std::optional<LSPAny>;
 
@@ -2876,8 +2864,7 @@ class WorkspaceSymbol final : public LSPObject {
 
   [[nodiscard]] auto containerName() const -> std::optional<std::string>;
 
-  auto location(
-      std::variant<std::monostate, Location, LocationUriOnly> location)
+  auto location(std::variant<Location, LocationUriOnly> location)
       -> WorkspaceSymbol&;
 
   auto data(std::optional<LSPAny> data) -> WorkspaceSymbol&;
@@ -2956,15 +2943,15 @@ class CodeLensRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto resolveProvider() const -> std::optional<bool>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> CodeLensRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> CodeLensRegistrationOptions&;
 
   auto resolveProvider(std::optional<bool> resolveProvider)
       -> CodeLensRegistrationOptions&;
@@ -3024,15 +3011,15 @@ class DocumentLinkRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto resolveProvider() const -> std::optional<bool>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DocumentLinkRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DocumentLinkRegistrationOptions&;
 
   auto resolveProvider(std::optional<bool> resolveProvider)
       -> DocumentLinkRegistrationOptions&;
@@ -3069,13 +3056,13 @@ class DocumentFormattingRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DocumentFormattingRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DocumentFormattingRegistrationOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> DocumentFormattingRegistrationOptions&;
@@ -3113,15 +3100,15 @@ class DocumentRangeFormattingRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto rangesSupport() const -> std::optional<bool>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DocumentRangeFormattingRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DocumentRangeFormattingRegistrationOptions&;
 
   auto rangesSupport(std::optional<bool> rangesSupport)
       -> DocumentRangeFormattingRegistrationOptions&;
@@ -3186,7 +3173,7 @@ class DocumentOnTypeFormattingRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto firstTriggerCharacter() const -> std::string;
 
@@ -3194,8 +3181,8 @@ class DocumentOnTypeFormattingRegistrationOptions final : public LSPObject {
       -> std::optional<Vector<std::string>>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> DocumentOnTypeFormattingRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> DocumentOnTypeFormattingRegistrationOptions&;
 
   auto firstTriggerCharacter(std::string firstTriggerCharacter)
       -> DocumentOnTypeFormattingRegistrationOptions&;
@@ -3236,15 +3223,15 @@ class RenameRegistrationOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto documentSelector() const
-      -> std::variant<std::monostate, DocumentSelector, std::nullptr_t>;
+      -> std::variant<DocumentSelector, std::nullptr_t>;
 
   [[nodiscard]] auto prepareProvider() const -> std::optional<bool>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto documentSelector(
-      std::variant<std::monostate, DocumentSelector, std::nullptr_t>
-          documentSelector) -> RenameRegistrationOptions&;
+      std::variant<DocumentSelector, std::nullptr_t> documentSelector)
+      -> RenameRegistrationOptions&;
 
   auto prepareProvider(std::optional<bool> prepareProvider)
       -> RenameRegistrationOptions&;
@@ -3450,10 +3437,9 @@ class CancelParams final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto id() const
-      -> std::variant<std::monostate, int, std::string>;
+  [[nodiscard]] auto id() const -> std::variant<int, std::string>;
 
-  auto id(std::variant<std::monostate, int, std::string> id) -> CancelParams&;
+  auto id(std::variant<int, std::string> id) -> CancelParams&;
 };
 
 class ProgressParams final : public LSPObject {
@@ -3732,22 +3718,20 @@ class SemanticTokensOptions final : public LSPObject {
 
   [[nodiscard]] auto legend() const -> SemanticTokensLegend;
 
-  [[nodiscard]] auto range() const
-      -> std::optional<std::variant<std::monostate, bool, json>>;
+  [[nodiscard]] auto range() const -> std::optional<std::variant<bool, json>>;
 
-  [[nodiscard]] auto full() const -> std::optional<
-      std::variant<std::monostate, bool, SemanticTokensFullDelta>>;
+  [[nodiscard]] auto full() const
+      -> std::optional<std::variant<bool, SemanticTokensFullDelta>>;
 
   [[nodiscard]] auto workDoneProgress() const -> std::optional<bool>;
 
   auto legend(SemanticTokensLegend legend) -> SemanticTokensOptions&;
 
-  auto range(std::optional<std::variant<std::monostate, bool, json>> range)
+  auto range(std::optional<std::variant<bool, json>> range)
       -> SemanticTokensOptions&;
 
-  auto full(
-      std::optional<std::variant<std::monostate, bool, SemanticTokensFullDelta>>
-          full) -> SemanticTokensOptions&;
+  auto full(std::optional<std::variant<bool, SemanticTokensFullDelta>> full)
+      -> SemanticTokensOptions&;
 
   auto workDoneProgress(std::optional<bool> workDoneProgress)
       -> SemanticTokensOptions&;
@@ -3805,15 +3789,14 @@ class TextDocumentEdit final : public LSPObject {
       -> OptionalVersionedTextDocumentIdentifier;
 
   [[nodiscard]] auto edits() const
-      -> Vector<std::variant<std::monostate, TextEdit, AnnotatedTextEdit,
-                             SnippetTextEdit>>;
+      -> Vector<std::variant<TextEdit, AnnotatedTextEdit, SnippetTextEdit>>;
 
   auto textDocument(OptionalVersionedTextDocumentIdentifier textDocument)
       -> TextDocumentEdit&;
 
-  auto edits(Vector<std::variant<std::monostate, TextEdit, AnnotatedTextEdit,
-                                 SnippetTextEdit>>
-                 edits) -> TextDocumentEdit&;
+  auto edits(
+      Vector<std::variant<TextEdit, AnnotatedTextEdit, SnippetTextEdit>> edits)
+      -> TextDocumentEdit&;
 };
 
 class CreateFile final : public LSPObject {
@@ -4067,8 +4050,8 @@ class InlayHintLabelPart final : public LSPObject {
 
   [[nodiscard]] auto value() const -> std::string;
 
-  [[nodiscard]] auto tooltip() const -> std::optional<
-      std::variant<std::monostate, std::string, MarkupContent>>;
+  [[nodiscard]] auto tooltip() const
+      -> std::optional<std::variant<std::string, MarkupContent>>;
 
   [[nodiscard]] auto location() const -> std::optional<Location>;
 
@@ -4076,9 +4059,8 @@ class InlayHintLabelPart final : public LSPObject {
 
   auto value(std::string value) -> InlayHintLabelPart&;
 
-  auto tooltip(
-      std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-          tooltip) -> InlayHintLabelPart&;
+  auto tooltip(std::optional<std::variant<std::string, MarkupContent>> tooltip)
+      -> InlayHintLabelPart&;
 
   auto location(std::optional<Location> location) -> InlayHintLabelPart&;
 
@@ -4123,9 +4105,9 @@ class RelatedFullDocumentDiagnosticReport final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto relatedDocuments() const -> std::optional<Map<
-      std::string, std::variant<std::monostate, FullDocumentDiagnosticReport,
-                                UnchangedDocumentDiagnosticReport>>>;
+  [[nodiscard]] auto relatedDocuments() const -> std::optional<
+      Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                    UnchangedDocumentDiagnosticReport>>>;
 
   [[nodiscard]] auto kind() const -> std::string;
 
@@ -4135,9 +4117,8 @@ class RelatedFullDocumentDiagnosticReport final : public LSPObject {
 
   auto relatedDocuments(
       std::optional<
-          Map<std::string,
-              std::variant<std::monostate, FullDocumentDiagnosticReport,
-                           UnchangedDocumentDiagnosticReport>>>
+          Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                        UnchangedDocumentDiagnosticReport>>>
           relatedDocuments) -> RelatedFullDocumentDiagnosticReport&;
 
   auto kind(std::string kind) -> RelatedFullDocumentDiagnosticReport&;
@@ -4154,9 +4135,9 @@ class RelatedUnchangedDocumentDiagnosticReport final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto relatedDocuments() const -> std::optional<Map<
-      std::string, std::variant<std::monostate, FullDocumentDiagnosticReport,
-                                UnchangedDocumentDiagnosticReport>>>;
+  [[nodiscard]] auto relatedDocuments() const -> std::optional<
+      Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                    UnchangedDocumentDiagnosticReport>>>;
 
   [[nodiscard]] auto kind() const -> std::string;
 
@@ -4164,9 +4145,8 @@ class RelatedUnchangedDocumentDiagnosticReport final : public LSPObject {
 
   auto relatedDocuments(
       std::optional<
-          Map<std::string,
-              std::variant<std::monostate, FullDocumentDiagnosticReport,
-                           UnchangedDocumentDiagnosticReport>>>
+          Map<std::string, std::variant<FullDocumentDiagnosticReport,
+                                        UnchangedDocumentDiagnosticReport>>>
           relatedDocuments) -> RelatedUnchangedDocumentDiagnosticReport&;
 
   auto kind(std::string kind) -> RelatedUnchangedDocumentDiagnosticReport&;
@@ -4306,15 +4286,14 @@ class NotebookDocumentSyncOptions final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto notebookSelector() const
-      -> Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
+      -> Vector<std::variant<NotebookDocumentFilterWithNotebook,
                              NotebookDocumentFilterWithCells>>;
 
   [[nodiscard]] auto save() const -> std::optional<bool>;
 
-  auto notebookSelector(
-      Vector<std::variant<std::monostate, NotebookDocumentFilterWithNotebook,
-                          NotebookDocumentFilterWithCells>>
-          notebookSelector) -> NotebookDocumentSyncOptions&;
+  auto notebookSelector(Vector<std::variant<NotebookDocumentFilterWithNotebook,
+                                            NotebookDocumentFilterWithCells>>
+                            notebookSelector) -> NotebookDocumentSyncOptions&;
 
   auto save(std::optional<bool> save) -> NotebookDocumentSyncOptions&;
 };
@@ -4460,18 +4439,17 @@ class _InitializeParams final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto processId() const
-      -> std::variant<std::monostate, int, std::nullptr_t>;
+  [[nodiscard]] auto processId() const -> std::variant<int, std::nullptr_t>;
 
   [[nodiscard]] auto clientInfo() const -> std::optional<ClientInfo>;
 
   [[nodiscard]] auto locale() const -> std::optional<std::string>;
 
-  [[nodiscard]] auto rootPath() const -> std::optional<
-      std::variant<std::monostate, std::string, std::nullptr_t>>;
+  [[nodiscard]] auto rootPath() const
+      -> std::optional<std::variant<std::string, std::nullptr_t>>;
 
   [[nodiscard]] auto rootUri() const
-      -> std::variant<std::monostate, std::string, std::nullptr_t>;
+      -> std::variant<std::string, std::nullptr_t>;
 
   [[nodiscard]] auto capabilities() const -> ClientCapabilities;
 
@@ -4481,7 +4459,7 @@ class _InitializeParams final : public LSPObject {
 
   [[nodiscard]] auto workDoneToken() const -> std::optional<ProgressToken>;
 
-  auto processId(std::variant<std::monostate, int, std::nullptr_t> processId)
+  auto processId(std::variant<int, std::nullptr_t> processId)
       -> _InitializeParams&;
 
   auto clientInfo(std::optional<ClientInfo> clientInfo) -> _InitializeParams&;
@@ -4489,11 +4467,10 @@ class _InitializeParams final : public LSPObject {
   auto locale(std::optional<std::string> locale) -> _InitializeParams&;
 
   auto rootPath(
-      std::optional<std::variant<std::monostate, std::string, std::nullptr_t>>
-          rootPath) -> _InitializeParams&;
+      std::optional<std::variant<std::string, std::nullptr_t>> rootPath)
+      -> _InitializeParams&;
 
-  auto rootUri(
-      std::variant<std::monostate, std::string, std::nullptr_t> rootUri)
+  auto rootUri(std::variant<std::string, std::nullptr_t> rootUri)
       -> _InitializeParams&;
 
   auto capabilities(ClientCapabilities capabilities) -> _InitializeParams&;
@@ -4513,12 +4490,11 @@ class WorkspaceFoldersInitializeParams final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto workspaceFolders() const -> std::optional<
-      std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t>>;
+  [[nodiscard]] auto workspaceFolders() const
+      -> std::optional<std::variant<Vector<WorkspaceFolder>, std::nullptr_t>>;
 
   auto workspaceFolders(
-      std::optional<
-          std::variant<std::monostate, Vector<WorkspaceFolder>, std::nullptr_t>>
+      std::optional<std::variant<Vector<WorkspaceFolder>, std::nullptr_t>>
           workspaceFolders) -> WorkspaceFoldersInitializeParams&;
 };
 
@@ -4531,49 +4507,47 @@ class ServerCapabilities final : public LSPObject {
   [[nodiscard]] auto positionEncoding() const
       -> std::optional<PositionEncodingKind>;
 
-  [[nodiscard]] auto textDocumentSync() const
-      -> std::optional<std::variant<std::monostate, TextDocumentSyncOptions,
-                                    TextDocumentSyncKind>>;
+  [[nodiscard]] auto textDocumentSync() const -> std::optional<
+      std::variant<TextDocumentSyncOptions, TextDocumentSyncKind>>;
 
   [[nodiscard]] auto notebookDocumentSync() const
-      -> std::optional<std::variant<std::monostate, NotebookDocumentSyncOptions,
+      -> std::optional<std::variant<NotebookDocumentSyncOptions,
                                     NotebookDocumentSyncRegistrationOptions>>;
 
   [[nodiscard]] auto completionProvider() const
       -> std::optional<CompletionOptions>;
 
   [[nodiscard]] auto hoverProvider() const
-      -> std::optional<std::variant<std::monostate, bool, HoverOptions>>;
+      -> std::optional<std::variant<bool, HoverOptions>>;
 
   [[nodiscard]] auto signatureHelpProvider() const
       -> std::optional<SignatureHelpOptions>;
 
-  [[nodiscard]] auto declarationProvider() const
-      -> std::optional<std::variant<std::monostate, bool, DeclarationOptions,
-                                    DeclarationRegistrationOptions>>;
+  [[nodiscard]] auto declarationProvider() const -> std::optional<
+      std::variant<bool, DeclarationOptions, DeclarationRegistrationOptions>>;
 
   [[nodiscard]] auto definitionProvider() const
-      -> std::optional<std::variant<std::monostate, bool, DefinitionOptions>>;
+      -> std::optional<std::variant<bool, DefinitionOptions>>;
 
   [[nodiscard]] auto typeDefinitionProvider() const
-      -> std::optional<std::variant<std::monostate, bool, TypeDefinitionOptions,
+      -> std::optional<std::variant<bool, TypeDefinitionOptions,
                                     TypeDefinitionRegistrationOptions>>;
 
   [[nodiscard]] auto implementationProvider() const
-      -> std::optional<std::variant<std::monostate, bool, ImplementationOptions,
+      -> std::optional<std::variant<bool, ImplementationOptions,
                                     ImplementationRegistrationOptions>>;
 
   [[nodiscard]] auto referencesProvider() const
-      -> std::optional<std::variant<std::monostate, bool, ReferenceOptions>>;
+      -> std::optional<std::variant<bool, ReferenceOptions>>;
 
-  [[nodiscard]] auto documentHighlightProvider() const -> std::optional<
-      std::variant<std::monostate, bool, DocumentHighlightOptions>>;
+  [[nodiscard]] auto documentHighlightProvider() const
+      -> std::optional<std::variant<bool, DocumentHighlightOptions>>;
 
-  [[nodiscard]] auto documentSymbolProvider() const -> std::optional<
-      std::variant<std::monostate, bool, DocumentSymbolOptions>>;
+  [[nodiscard]] auto documentSymbolProvider() const
+      -> std::optional<std::variant<bool, DocumentSymbolOptions>>;
 
   [[nodiscard]] auto codeActionProvider() const
-      -> std::optional<std::variant<std::monostate, bool, CodeActionOptions>>;
+      -> std::optional<std::variant<bool, CodeActionOptions>>;
 
   [[nodiscard]] auto codeLensProvider() const -> std::optional<CodeLensOptions>;
 
@@ -4581,69 +4555,63 @@ class ServerCapabilities final : public LSPObject {
       -> std::optional<DocumentLinkOptions>;
 
   [[nodiscard]] auto colorProvider() const
-      -> std::optional<std::variant<std::monostate, bool, DocumentColorOptions,
+      -> std::optional<std::variant<bool, DocumentColorOptions,
                                     DocumentColorRegistrationOptions>>;
 
-  [[nodiscard]] auto workspaceSymbolProvider() const -> std::optional<
-      std::variant<std::monostate, bool, WorkspaceSymbolOptions>>;
+  [[nodiscard]] auto workspaceSymbolProvider() const
+      -> std::optional<std::variant<bool, WorkspaceSymbolOptions>>;
 
-  [[nodiscard]] auto documentFormattingProvider() const -> std::optional<
-      std::variant<std::monostate, bool, DocumentFormattingOptions>>;
+  [[nodiscard]] auto documentFormattingProvider() const
+      -> std::optional<std::variant<bool, DocumentFormattingOptions>>;
 
-  [[nodiscard]] auto documentRangeFormattingProvider() const -> std::optional<
-      std::variant<std::monostate, bool, DocumentRangeFormattingOptions>>;
+  [[nodiscard]] auto documentRangeFormattingProvider() const
+      -> std::optional<std::variant<bool, DocumentRangeFormattingOptions>>;
 
   [[nodiscard]] auto documentOnTypeFormattingProvider() const
       -> std::optional<DocumentOnTypeFormattingOptions>;
 
   [[nodiscard]] auto renameProvider() const
-      -> std::optional<std::variant<std::monostate, bool, RenameOptions>>;
+      -> std::optional<std::variant<bool, RenameOptions>>;
 
-  [[nodiscard]] auto foldingRangeProvider() const
-      -> std::optional<std::variant<std::monostate, bool, FoldingRangeOptions,
-                                    FoldingRangeRegistrationOptions>>;
+  [[nodiscard]] auto foldingRangeProvider() const -> std::optional<
+      std::variant<bool, FoldingRangeOptions, FoldingRangeRegistrationOptions>>;
 
   [[nodiscard]] auto selectionRangeProvider() const
-      -> std::optional<std::variant<std::monostate, bool, SelectionRangeOptions,
+      -> std::optional<std::variant<bool, SelectionRangeOptions,
                                     SelectionRangeRegistrationOptions>>;
 
   [[nodiscard]] auto executeCommandProvider() const
       -> std::optional<ExecuteCommandOptions>;
 
   [[nodiscard]] auto callHierarchyProvider() const
-      -> std::optional<std::variant<std::monostate, bool, CallHierarchyOptions,
+      -> std::optional<std::variant<bool, CallHierarchyOptions,
                                     CallHierarchyRegistrationOptions>>;
 
-  [[nodiscard]] auto linkedEditingRangeProvider() const -> std::optional<
-      std::variant<std::monostate, bool, LinkedEditingRangeOptions,
-                   LinkedEditingRangeRegistrationOptions>>;
+  [[nodiscard]] auto linkedEditingRangeProvider() const
+      -> std::optional<std::variant<bool, LinkedEditingRangeOptions,
+                                    LinkedEditingRangeRegistrationOptions>>;
 
-  [[nodiscard]] auto semanticTokensProvider() const
-      -> std::optional<std::variant<std::monostate, SemanticTokensOptions,
-                                    SemanticTokensRegistrationOptions>>;
+  [[nodiscard]] auto semanticTokensProvider() const -> std::optional<
+      std::variant<SemanticTokensOptions, SemanticTokensRegistrationOptions>>;
 
-  [[nodiscard]] auto monikerProvider() const
-      -> std::optional<std::variant<std::monostate, bool, MonikerOptions,
-                                    MonikerRegistrationOptions>>;
+  [[nodiscard]] auto monikerProvider() const -> std::optional<
+      std::variant<bool, MonikerOptions, MonikerRegistrationOptions>>;
 
   [[nodiscard]] auto typeHierarchyProvider() const
-      -> std::optional<std::variant<std::monostate, bool, TypeHierarchyOptions,
+      -> std::optional<std::variant<bool, TypeHierarchyOptions,
                                     TypeHierarchyRegistrationOptions>>;
 
-  [[nodiscard]] auto inlineValueProvider() const
-      -> std::optional<std::variant<std::monostate, bool, InlineValueOptions,
-                                    InlineValueRegistrationOptions>>;
+  [[nodiscard]] auto inlineValueProvider() const -> std::optional<
+      std::variant<bool, InlineValueOptions, InlineValueRegistrationOptions>>;
 
-  [[nodiscard]] auto inlayHintProvider() const
-      -> std::optional<std::variant<std::monostate, bool, InlayHintOptions,
-                                    InlayHintRegistrationOptions>>;
+  [[nodiscard]] auto inlayHintProvider() const -> std::optional<
+      std::variant<bool, InlayHintOptions, InlayHintRegistrationOptions>>;
 
-  [[nodiscard]] auto diagnosticProvider() const
-      -> std::optional<std::variant<std::monostate, DiagnosticOptions,
-                                    DiagnosticRegistrationOptions>>;
+  [[nodiscard]] auto diagnosticProvider() const -> std::optional<
+      std::variant<DiagnosticOptions, DiagnosticRegistrationOptions>>;
 
-  [[nodiscard]] auto inlineCompletionProvider() const -> std::optional<
-      std::variant<std::monostate, bool, InlineCompletionOptions>>;
+  [[nodiscard]] auto inlineCompletionProvider() const
+      -> std::optional<std::variant<bool, InlineCompletionOptions>>;
 
   [[nodiscard]] auto workspace() const -> std::optional<WorkspaceOptions>;
 
@@ -4653,12 +4621,11 @@ class ServerCapabilities final : public LSPObject {
       -> ServerCapabilities&;
 
   auto textDocumentSync(
-      std::optional<std::variant<std::monostate, TextDocumentSyncOptions,
-                                 TextDocumentSyncKind>>
+      std::optional<std::variant<TextDocumentSyncOptions, TextDocumentSyncKind>>
           textDocumentSync) -> ServerCapabilities&;
 
   auto notebookDocumentSync(
-      std::optional<std::variant<std::monostate, NotebookDocumentSyncOptions,
+      std::optional<std::variant<NotebookDocumentSyncOptions,
                                  NotebookDocumentSyncRegistrationOptions>>
           notebookDocumentSync) -> ServerCapabilities&;
 
@@ -4666,48 +4633,47 @@ class ServerCapabilities final : public LSPObject {
       -> ServerCapabilities&;
 
   auto hoverProvider(
-      std::optional<std::variant<std::monostate, bool, HoverOptions>>
-          hoverProvider) -> ServerCapabilities&;
+      std::optional<std::variant<bool, HoverOptions>> hoverProvider)
+      -> ServerCapabilities&;
 
   auto signatureHelpProvider(
       std::optional<SignatureHelpOptions> signatureHelpProvider)
       -> ServerCapabilities&;
 
   auto declarationProvider(
-      std::optional<std::variant<std::monostate, bool, DeclarationOptions,
+      std::optional<std::variant<bool, DeclarationOptions,
                                  DeclarationRegistrationOptions>>
           declarationProvider) -> ServerCapabilities&;
 
   auto definitionProvider(
-      std::optional<std::variant<std::monostate, bool, DefinitionOptions>>
-          definitionProvider) -> ServerCapabilities&;
+      std::optional<std::variant<bool, DefinitionOptions>> definitionProvider)
+      -> ServerCapabilities&;
 
   auto typeDefinitionProvider(
-      std::optional<std::variant<std::monostate, bool, TypeDefinitionOptions,
+      std::optional<std::variant<bool, TypeDefinitionOptions,
                                  TypeDefinitionRegistrationOptions>>
           typeDefinitionProvider) -> ServerCapabilities&;
 
   auto implementationProvider(
-      std::optional<std::variant<std::monostate, bool, ImplementationOptions,
+      std::optional<std::variant<bool, ImplementationOptions,
                                  ImplementationRegistrationOptions>>
           implementationProvider) -> ServerCapabilities&;
 
   auto referencesProvider(
-      std::optional<std::variant<std::monostate, bool, ReferenceOptions>>
-          referencesProvider) -> ServerCapabilities&;
+      std::optional<std::variant<bool, ReferenceOptions>> referencesProvider)
+      -> ServerCapabilities&;
 
   auto documentHighlightProvider(
-      std::optional<
-          std::variant<std::monostate, bool, DocumentHighlightOptions>>
+      std::optional<std::variant<bool, DocumentHighlightOptions>>
           documentHighlightProvider) -> ServerCapabilities&;
 
   auto documentSymbolProvider(
-      std::optional<std::variant<std::monostate, bool, DocumentSymbolOptions>>
+      std::optional<std::variant<bool, DocumentSymbolOptions>>
           documentSymbolProvider) -> ServerCapabilities&;
 
   auto codeActionProvider(
-      std::optional<std::variant<std::monostate, bool, CodeActionOptions>>
-          codeActionProvider) -> ServerCapabilities&;
+      std::optional<std::variant<bool, CodeActionOptions>> codeActionProvider)
+      -> ServerCapabilities&;
 
   auto codeLensProvider(std::optional<CodeLensOptions> codeLensProvider)
       -> ServerCapabilities&;
@@ -4717,22 +4683,20 @@ class ServerCapabilities final : public LSPObject {
       -> ServerCapabilities&;
 
   auto colorProvider(
-      std::optional<std::variant<std::monostate, bool, DocumentColorOptions,
+      std::optional<std::variant<bool, DocumentColorOptions,
                                  DocumentColorRegistrationOptions>>
           colorProvider) -> ServerCapabilities&;
 
   auto workspaceSymbolProvider(
-      std::optional<std::variant<std::monostate, bool, WorkspaceSymbolOptions>>
+      std::optional<std::variant<bool, WorkspaceSymbolOptions>>
           workspaceSymbolProvider) -> ServerCapabilities&;
 
   auto documentFormattingProvider(
-      std::optional<
-          std::variant<std::monostate, bool, DocumentFormattingOptions>>
+      std::optional<std::variant<bool, DocumentFormattingOptions>>
           documentFormattingProvider) -> ServerCapabilities&;
 
   auto documentRangeFormattingProvider(
-      std::optional<
-          std::variant<std::monostate, bool, DocumentRangeFormattingOptions>>
+      std::optional<std::variant<bool, DocumentRangeFormattingOptions>>
           documentRangeFormattingProvider) -> ServerCapabilities&;
 
   auto documentOnTypeFormattingProvider(
@@ -4740,16 +4704,16 @@ class ServerCapabilities final : public LSPObject {
           documentOnTypeFormattingProvider) -> ServerCapabilities&;
 
   auto renameProvider(
-      std::optional<std::variant<std::monostate, bool, RenameOptions>>
-          renameProvider) -> ServerCapabilities&;
+      std::optional<std::variant<bool, RenameOptions>> renameProvider)
+      -> ServerCapabilities&;
 
   auto foldingRangeProvider(
-      std::optional<std::variant<std::monostate, bool, FoldingRangeOptions,
+      std::optional<std::variant<bool, FoldingRangeOptions,
                                  FoldingRangeRegistrationOptions>>
           foldingRangeProvider) -> ServerCapabilities&;
 
   auto selectionRangeProvider(
-      std::optional<std::variant<std::monostate, bool, SelectionRangeOptions,
+      std::optional<std::variant<bool, SelectionRangeOptions,
                                  SelectionRangeRegistrationOptions>>
           selectionRangeProvider) -> ServerCapabilities&;
 
@@ -4758,48 +4722,47 @@ class ServerCapabilities final : public LSPObject {
       -> ServerCapabilities&;
 
   auto callHierarchyProvider(
-      std::optional<std::variant<std::monostate, bool, CallHierarchyOptions,
+      std::optional<std::variant<bool, CallHierarchyOptions,
                                  CallHierarchyRegistrationOptions>>
           callHierarchyProvider) -> ServerCapabilities&;
 
   auto linkedEditingRangeProvider(
-      std::optional<
-          std::variant<std::monostate, bool, LinkedEditingRangeOptions,
-                       LinkedEditingRangeRegistrationOptions>>
+      std::optional<std::variant<bool, LinkedEditingRangeOptions,
+                                 LinkedEditingRangeRegistrationOptions>>
           linkedEditingRangeProvider) -> ServerCapabilities&;
 
   auto semanticTokensProvider(
-      std::optional<std::variant<std::monostate, SemanticTokensOptions,
+      std::optional<std::variant<SemanticTokensOptions,
                                  SemanticTokensRegistrationOptions>>
           semanticTokensProvider) -> ServerCapabilities&;
 
   auto monikerProvider(
-      std::optional<std::variant<std::monostate, bool, MonikerOptions,
-                                 MonikerRegistrationOptions>>
+      std::optional<
+          std::variant<bool, MonikerOptions, MonikerRegistrationOptions>>
           monikerProvider) -> ServerCapabilities&;
 
   auto typeHierarchyProvider(
-      std::optional<std::variant<std::monostate, bool, TypeHierarchyOptions,
+      std::optional<std::variant<bool, TypeHierarchyOptions,
                                  TypeHierarchyRegistrationOptions>>
           typeHierarchyProvider) -> ServerCapabilities&;
 
   auto inlineValueProvider(
-      std::optional<std::variant<std::monostate, bool, InlineValueOptions,
+      std::optional<std::variant<bool, InlineValueOptions,
                                  InlineValueRegistrationOptions>>
           inlineValueProvider) -> ServerCapabilities&;
 
   auto inlayHintProvider(
-      std::optional<std::variant<std::monostate, bool, InlayHintOptions,
-                                 InlayHintRegistrationOptions>>
+      std::optional<
+          std::variant<bool, InlayHintOptions, InlayHintRegistrationOptions>>
           inlayHintProvider) -> ServerCapabilities&;
 
   auto diagnosticProvider(
-      std::optional<std::variant<std::monostate, DiagnosticOptions,
-                                 DiagnosticRegistrationOptions>>
+      std::optional<
+          std::variant<DiagnosticOptions, DiagnosticRegistrationOptions>>
           diagnosticProvider) -> ServerCapabilities&;
 
   auto inlineCompletionProvider(
-      std::optional<std::variant<std::monostate, bool, InlineCompletionOptions>>
+      std::optional<std::variant<bool, InlineCompletionOptions>>
           inlineCompletionProvider) -> ServerCapabilities&;
 
   auto workspace(std::optional<WorkspaceOptions> workspace)
@@ -4890,7 +4853,7 @@ class Diagnostic final : public LSPObject {
   [[nodiscard]] auto severity() const -> std::optional<DiagnosticSeverity>;
 
   [[nodiscard]] auto code() const
-      -> std::optional<std::variant<std::monostate, int, std::string>>;
+      -> std::optional<std::variant<int, std::string>>;
 
   [[nodiscard]] auto codeDescription() const -> std::optional<CodeDescription>;
 
@@ -4909,8 +4872,7 @@ class Diagnostic final : public LSPObject {
 
   auto severity(std::optional<DiagnosticSeverity> severity) -> Diagnostic&;
 
-  auto code(std::optional<std::variant<std::monostate, int, std::string>> code)
-      -> Diagnostic&;
+  auto code(std::optional<std::variant<int, std::string>> code) -> Diagnostic&;
 
   auto codeDescription(std::optional<CodeDescription> codeDescription)
       -> Diagnostic&;
@@ -4988,8 +4950,8 @@ class CompletionItemDefaults final : public LSPObject {
   [[nodiscard]] auto commitCharacters() const
       -> std::optional<Vector<std::string>>;
 
-  [[nodiscard]] auto editRange() const -> std::optional<
-      std::variant<std::monostate, Range, EditRangeWithInsertReplace>>;
+  [[nodiscard]] auto editRange() const
+      -> std::optional<std::variant<Range, EditRangeWithInsertReplace>>;
 
   [[nodiscard]] auto insertTextFormat() const
       -> std::optional<InsertTextFormat>;
@@ -5002,9 +4964,8 @@ class CompletionItemDefaults final : public LSPObject {
       -> CompletionItemDefaults&;
 
   auto editRange(
-      std::optional<
-          std::variant<std::monostate, Range, EditRangeWithInsertReplace>>
-          editRange) -> CompletionItemDefaults&;
+      std::optional<std::variant<Range, EditRangeWithInsertReplace>> editRange)
+      -> CompletionItemDefaults&;
 
   auto insertTextFormat(std::optional<InsertTextFormat> insertTextFormat)
       -> CompletionItemDefaults&;
@@ -5113,27 +5074,27 @@ class SignatureInformation final : public LSPObject {
 
   [[nodiscard]] auto label() const -> std::string;
 
-  [[nodiscard]] auto documentation() const -> std::optional<
-      std::variant<std::monostate, std::string, MarkupContent>>;
+  [[nodiscard]] auto documentation() const
+      -> std::optional<std::variant<std::string, MarkupContent>>;
 
   [[nodiscard]] auto parameters() const
       -> std::optional<Vector<ParameterInformation>>;
 
   [[nodiscard]] auto activeParameter() const
-      -> std::optional<std::variant<std::monostate, long, std::nullptr_t>>;
+      -> std::optional<std::variant<long, std::nullptr_t>>;
 
   auto label(std::string label) -> SignatureInformation&;
 
   auto documentation(
-      std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-          documentation) -> SignatureInformation&;
+      std::optional<std::variant<std::string, MarkupContent>> documentation)
+      -> SignatureInformation&;
 
   auto parameters(std::optional<Vector<ParameterInformation>> parameters)
       -> SignatureInformation&;
 
   auto activeParameter(
-      std::optional<std::variant<std::monostate, long, std::nullptr_t>>
-          activeParameter) -> SignatureInformation&;
+      std::optional<std::variant<long, std::nullptr_t>> activeParameter)
+      -> SignatureInformation&;
 };
 
 class SignatureHelpOptions final : public LSPObject {
@@ -5551,12 +5512,11 @@ class OptionalVersionedTextDocumentIdentifier final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto version() const
-      -> std::variant<std::monostate, int, std::nullptr_t>;
+  [[nodiscard]] auto version() const -> std::variant<int, std::nullptr_t>;
 
   [[nodiscard]] auto uri() const -> std::string;
 
-  auto version(std::variant<std::monostate, int, std::nullptr_t> version)
+  auto version(std::variant<int, std::nullptr_t> version)
       -> OptionalVersionedTextDocumentIdentifier&;
 
   auto uri(std::string uri) -> OptionalVersionedTextDocumentIdentifier&;
@@ -5696,8 +5656,7 @@ class WorkspaceFullDocumentDiagnosticReport final : public LSPObject {
 
   [[nodiscard]] auto uri() const -> std::string;
 
-  [[nodiscard]] auto version() const
-      -> std::variant<std::monostate, int, std::nullptr_t>;
+  [[nodiscard]] auto version() const -> std::variant<int, std::nullptr_t>;
 
   [[nodiscard]] auto kind() const -> std::string;
 
@@ -5707,7 +5666,7 @@ class WorkspaceFullDocumentDiagnosticReport final : public LSPObject {
 
   auto uri(std::string uri) -> WorkspaceFullDocumentDiagnosticReport&;
 
-  auto version(std::variant<std::monostate, int, std::nullptr_t> version)
+  auto version(std::variant<int, std::nullptr_t> version)
       -> WorkspaceFullDocumentDiagnosticReport&;
 
   auto kind(std::string kind) -> WorkspaceFullDocumentDiagnosticReport&;
@@ -5727,8 +5686,7 @@ class WorkspaceUnchangedDocumentDiagnosticReport final : public LSPObject {
 
   [[nodiscard]] auto uri() const -> std::string;
 
-  [[nodiscard]] auto version() const
-      -> std::variant<std::monostate, int, std::nullptr_t>;
+  [[nodiscard]] auto version() const -> std::variant<int, std::nullptr_t>;
 
   [[nodiscard]] auto kind() const -> std::string;
 
@@ -5736,7 +5694,7 @@ class WorkspaceUnchangedDocumentDiagnosticReport final : public LSPObject {
 
   auto uri(std::string uri) -> WorkspaceUnchangedDocumentDiagnosticReport&;
 
-  auto version(std::variant<std::monostate, int, std::nullptr_t> version)
+  auto version(std::variant<int, std::nullptr_t> version)
       -> WorkspaceUnchangedDocumentDiagnosticReport&;
 
   auto kind(std::string kind) -> WorkspaceUnchangedDocumentDiagnosticReport&;
@@ -5777,14 +5735,13 @@ class NotebookDocumentFilterWithNotebook final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto notebook() const
-      -> std::variant<std::monostate, std::string, NotebookDocumentFilter>;
+      -> std::variant<std::string, NotebookDocumentFilter>;
 
   [[nodiscard]] auto cells() const
       -> std::optional<Vector<NotebookCellLanguage>>;
 
-  auto notebook(
-      std::variant<std::monostate, std::string, NotebookDocumentFilter>
-          notebook) -> NotebookDocumentFilterWithNotebook&;
+  auto notebook(std::variant<std::string, NotebookDocumentFilter> notebook)
+      -> NotebookDocumentFilterWithNotebook&;
 
   auto cells(std::optional<Vector<NotebookCellLanguage>> cells)
       -> NotebookDocumentFilterWithNotebook&;
@@ -5796,15 +5753,14 @@ class NotebookDocumentFilterWithCells final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto notebook() const -> std::optional<
-      std::variant<std::monostate, std::string, NotebookDocumentFilter>>;
+  [[nodiscard]] auto notebook() const
+      -> std::optional<std::variant<std::string, NotebookDocumentFilter>>;
 
   [[nodiscard]] auto cells() const -> Vector<NotebookCellLanguage>;
 
   auto notebook(
-      std::optional<
-          std::variant<std::monostate, std::string, NotebookDocumentFilter>>
-          notebook) -> NotebookDocumentFilterWithCells&;
+      std::optional<std::variant<std::string, NotebookDocumentFilter>> notebook)
+      -> NotebookDocumentFilterWithCells&;
 
   auto cells(Vector<NotebookCellLanguage> cells)
       -> NotebookDocumentFilterWithCells&;
@@ -5921,7 +5877,7 @@ class TextDocumentSyncOptions final : public LSPObject {
   [[nodiscard]] auto willSaveWaitUntil() const -> std::optional<bool>;
 
   [[nodiscard]] auto save() const
-      -> std::optional<std::variant<std::monostate, bool, SaveOptions>>;
+      -> std::optional<std::variant<bool, SaveOptions>>;
 
   auto openClose(std::optional<bool> openClose) -> TextDocumentSyncOptions&;
 
@@ -5933,7 +5889,7 @@ class TextDocumentSyncOptions final : public LSPObject {
   auto willSaveWaitUntil(std::optional<bool> willSaveWaitUntil)
       -> TextDocumentSyncOptions&;
 
-  auto save(std::optional<std::variant<std::monostate, bool, SaveOptions>> save)
+  auto save(std::optional<std::variant<bool, SaveOptions>> save)
       -> TextDocumentSyncOptions&;
 };
 
@@ -5950,7 +5906,7 @@ class WorkspaceOptions final : public LSPObject {
       -> std::optional<FileOperationOptions>;
 
   [[nodiscard]] auto textDocumentContent() const
-      -> std::optional<std::variant<std::monostate, TextDocumentContentOptions,
+      -> std::optional<std::variant<TextDocumentContentOptions,
                                     TextDocumentContentRegistrationOptions>>;
 
   auto workspaceFolders(
@@ -5961,7 +5917,7 @@ class WorkspaceOptions final : public LSPObject {
       -> WorkspaceOptions&;
 
   auto textDocumentContent(
-      std::optional<std::variant<std::monostate, TextDocumentContentOptions,
+      std::optional<std::variant<TextDocumentContentOptions,
                                  TextDocumentContentRegistrationOptions>>
           textDocumentContent) -> WorkspaceOptions&;
 };
@@ -6072,18 +6028,17 @@ class ParameterInformation final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto label() const
-      -> std::variant<std::monostate, std::string, std::tuple<long, long>>;
+      -> std::variant<std::string, std::tuple<long, long>>;
 
-  [[nodiscard]] auto documentation() const -> std::optional<
-      std::variant<std::monostate, std::string, MarkupContent>>;
+  [[nodiscard]] auto documentation() const
+      -> std::optional<std::variant<std::string, MarkupContent>>;
 
-  auto label(
-      std::variant<std::monostate, std::string, std::tuple<long, long>> label)
+  auto label(std::variant<std::string, std::tuple<long, long>> label)
       -> ParameterInformation&;
 
   auto documentation(
-      std::optional<std::variant<std::monostate, std::string, MarkupContent>>
-          documentation) -> ParameterInformation&;
+      std::optional<std::variant<std::string, MarkupContent>> documentation)
+      -> ParameterInformation&;
 };
 
 class CodeActionKindDocumentation final : public LSPObject {
@@ -6108,13 +6063,12 @@ class NotebookCellTextDocumentFilter final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto notebook() const
-      -> std::variant<std::monostate, std::string, NotebookDocumentFilter>;
+      -> std::variant<std::string, NotebookDocumentFilter>;
 
   [[nodiscard]] auto language() const -> std::optional<std::string>;
 
-  auto notebook(
-      std::variant<std::monostate, std::string, NotebookDocumentFilter>
-          notebook) -> NotebookCellTextDocumentFilter&;
+  auto notebook(std::variant<std::string, NotebookDocumentFilter> notebook)
+      -> NotebookCellTextDocumentFilter&;
 
   auto language(std::optional<std::string> language)
       -> NotebookCellTextDocumentFilter&;
@@ -6602,14 +6556,14 @@ class WorkspaceFoldersServerCapabilities final : public LSPObject {
   [[nodiscard]] auto supported() const -> std::optional<bool>;
 
   [[nodiscard]] auto changeNotifications() const
-      -> std::optional<std::variant<std::monostate, std::string, bool>>;
+      -> std::optional<std::variant<std::string, bool>>;
 
   auto supported(std::optional<bool> supported)
       -> WorkspaceFoldersServerCapabilities&;
 
   auto changeNotifications(
-      std::optional<std::variant<std::monostate, std::string, bool>>
-          changeNotifications) -> WorkspaceFoldersServerCapabilities&;
+      std::optional<std::variant<std::string, bool>> changeNotifications)
+      -> WorkspaceFoldersServerCapabilities&;
 };
 
 class FileOperationOptions final : public LSPObject {
@@ -6662,12 +6616,11 @@ class RelativePattern final : public LSPObject {
   explicit operator bool() const;
 
   [[nodiscard]] auto baseUri() const
-      -> std::variant<std::monostate, WorkspaceFolder, std::string>;
+      -> std::variant<WorkspaceFolder, std::string>;
 
   [[nodiscard]] auto pattern() const -> Pattern;
 
-  auto baseUri(
-      std::variant<std::monostate, WorkspaceFolder, std::string> baseUri)
+  auto baseUri(std::variant<WorkspaceFolder, std::string> baseUri)
       -> RelativePattern&;
 
   auto pattern(Pattern pattern) -> RelativePattern&;
@@ -8118,18 +8071,17 @@ class ClientSemanticTokensRequestOptions final : public LSPObject {
 
   explicit operator bool() const;
 
-  [[nodiscard]] auto range() const
-      -> std::optional<std::variant<std::monostate, bool, json>>;
+  [[nodiscard]] auto range() const -> std::optional<std::variant<bool, json>>;
 
   [[nodiscard]] auto full() const -> std::optional<
-      std::variant<std::monostate, bool, ClientSemanticTokensRequestFullDelta>>;
+      std::variant<bool, ClientSemanticTokensRequestFullDelta>>;
 
-  auto range(std::optional<std::variant<std::monostate, bool, json>> range)
+  auto range(std::optional<std::variant<bool, json>> range)
       -> ClientSemanticTokensRequestOptions&;
 
-  auto full(std::optional<std::variant<std::monostate, bool,
-                                       ClientSemanticTokensRequestFullDelta>>
-                full) -> ClientSemanticTokensRequestOptions&;
+  auto full(
+      std::optional<std::variant<bool, ClientSemanticTokensRequestFullDelta>>
+          full) -> ClientSemanticTokensRequestOptions&;
 };
 
 class ClientInlayHintResolveOptions final : public LSPObject {
diff --git a/src/lsp/tests/test_types.cc b/src/lsp/tests/test_types.cc
index e65f0ec3..cf7b4532 100644
--- a/src/lsp/tests/test_types.cc
+++ b/src/lsp/tests/test_types.cc
@@ -4,9 +4,9 @@
 #include "cxx/lsp/enums.h"
 #include "cxx/lsp/fwd.h"
 
-TEST(SampleTest, AssertionTrue) {
-  using namespace cxx::lsp;
+using namespace cxx::lsp;
 
+TEST(LSP, Initialization) {
   // storage
   auto store1 = json::object();
   auto store2 = json::object();
@@ -41,3 +41,52 @@ TEST(SampleTest, AssertionTrue) {
 
   ASSERT_TRUE(initializeResult);
 }
+
+TEST(LSP, ArrayProperty) {
+  json storage = json::object();
+
+  ConfigurationParams configurationParams{storage};
+
+  ASSERT_FALSE(configurationParams);
+
+  auto items = configurationParams.items();
+
+  ASSERT_TRUE(items.empty());
+
+  ASSERT_TRUE(configurationParams);
+}
+
+TEST(LSP, MapProperty) {
+  json storage = json::object();
+
+  DocumentDiagnosticReportPartialResult documentDiagnosticReportPartialResult{
+      storage};
+
+  ASSERT_FALSE(documentDiagnosticReportPartialResult);
+
+  auto relatedDocuments =
+      documentDiagnosticReportPartialResult.relatedDocuments();
+
+  ASSERT_TRUE(relatedDocuments.empty());
+
+  ASSERT_TRUE(documentDiagnosticReportPartialResult);
+}
+
+TEST(LSP, StringProperty) {
+  json storage = json::object();
+
+  Location location{storage};
+
+  ASSERT_FALSE(location);
+
+  ASSERT_EQ(location.uri(), "");
+
+  location.uri("file:///path/to/file");
+  ASSERT_EQ(location.uri(), "file:///path/to/file");
+
+  auto range = location.range();
+  ASSERT_EQ(range.start().line(), 0);
+  ASSERT_EQ(range.start().character(), 0);
+
+  ASSERT_TRUE(location);
+}
\ No newline at end of file