diff --git a/schema.d.ts b/schema.d.ts
index 6f06c0b..3ad53ae 100644
--- a/schema.d.ts
+++ b/schema.d.ts
@@ -552,6 +552,11 @@ export interface PropertyLike {
    * If the value is a string, it's the reason for the deprecation.
    */
   deprecated?: boolean | string;
+
+  /**
+   * Whether the property is read-only.
+   */
+  readonly?: boolean;
 }
 
 export interface ClassField extends PropertyLike {
diff --git a/schema.json b/schema.json
index 3fd0d81..c533341 100644
--- a/schema.json
+++ b/schema.json
@@ -133,6 +133,10 @@
                 "privacy": {
                     "$ref": "#/definitions/Privacy"
                 },
+                "readonly": {
+                    "description": "Whether the property is read-only.",
+                    "type": "boolean"
+                },
                 "source": {
                     "$ref": "#/definitions/SourceReference"
                 },
@@ -881,6 +885,10 @@
                     "description": "Whether the parameter is optional. Undefined implies non-optional.",
                     "type": "boolean"
                 },
+                "readonly": {
+                    "description": "Whether the property is read-only.",
+                    "type": "boolean"
+                },
                 "rest": {
                     "description": "Whether the parameter is a rest parameter. Only the last parameter may be a rest parameter.\nUndefined implies single parameter.",
                     "type": "boolean"
@@ -1035,6 +1043,10 @@
                 "name": {
                     "type": "string"
                 },
+                "readonly": {
+                    "description": "Whether the property is read-only.",
+                    "type": "boolean"
+                },
                 "source": {
                     "$ref": "#/definitions/SourceReference"
                 },