mcp: add Server.AddRawTool, which is a better name for AddTool

examples/server/toolschemas/main.go

@@ -139,7 +139,7 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	server.AddTool(&mcp.Tool{
+	server.AddRawTool(&mcp.Tool{
 		Name:         "manual greeting",
 		InputSchema:  inputSchema,
 		OutputSchema: outputSchema,

mcp/mcp_test.go

@@ -277,7 +277,7 @@ func TestEndToEnd(t *testing.T) {
 		}
 
 		// Check tools-changed notifications.
-		s.AddTool(&Tool{Name: "T", InputSchema: &jsonschema.Schema{Type: "object"}}, nopHandler)
+		s.AddRawTool(&Tool{Name: "T", InputSchema: &jsonschema.Schema{Type: "object"}}, nopHandler)
 		waitForNotification(t, "tools")
 		s.RemoveTools("T")
 		waitForNotification(t, "tools")
@@ -1525,8 +1525,8 @@ func TestAddTool_DuplicateNoPanicAndNoDuplicate(t *testing.T) {
 		// This case was written specifically to reproduce a bug where duplicate tools where causing jsonschema errors
 		t1 := &Tool{Name: "dup", Description: "first", InputSchema: &jsonschema.Schema{Type: "object"}}
 		t2 := &Tool{Name: "dup", Description: "second", InputSchema: &jsonschema.Schema{Type: "object"}}
-		s.AddTool(t1, nopHandler)
-		s.AddTool(t2, nopHandler)
+		s.AddRawTool(t1, nopHandler)
+		s.AddRawTool(t2, nopHandler)
 	})
 	defer cleanup()
 

mcp/server.go

@@ -159,7 +159,18 @@ func (s *Server) RemovePrompts(names ...string) {
 		func() bool { return s.prompts.remove(names...) })
 }
 
-// AddTool adds a [Tool] to the server, or replaces one with the same name.
+// AddTool was a misnamed way to add a 'raw' tool, that doesn't perform any
+// parsing or validation validation. It is being renamed to AddRawTool so that
+// AddTool is available in the future (see #530).
+//
+// Deprecated: use AddRawTool. AddTool will be remove for v1.0.0.
+//
+//go:fix inline
+func (s *Server) AddTool(t *Tool, h ToolHandler) {
+	s.AddRawTool(t, h)
+}
+
+// AddRawTool adds a [Tool] to the server, or replaces one with the same name.
 // The Tool argument must not be modified after this call.
 //
 // The tool's input schema must be non-nil and have the type "object". For a tool
@@ -179,9 +190,9 @@ func (s *Server) RemovePrompts(names ...string) {
 // Setting the result's Content, StructuredContent and IsError fields are the caller's
 // responsibility.
 //
-// Most users should use the top-level function [AddTool], which handles all these
+// Most users should use the top-level function [AddRawTool], which handles all these
 // responsibilities.
-func (s *Server) AddTool(t *Tool, h ToolHandler) {
+func (s *Server) AddRawTool(t *Tool, h ToolHandler) {
 	if t.InputSchema == nil {
 		// This prevents the tool author from forgetting to write a schema where
 		// one should be provided. If we papered over this by supplying the empty
@@ -358,15 +369,15 @@ func setSchema[T any](sfield **jsonschema.Schema, rfield **jsonschema.Resolved)
 // output schema is set to the schema inferred from the Out type argument,
 // which also must be a map or struct.
 //
-// Unlike [Server.AddTool], AddTool does a lot automatically, and forces tools
+// Unlike [Server.AddRawTool], AddTool does a lot automatically, and forces tools
 // to conform to the MCP spec. See [ToolHandlerFor] for a detailed description
 // of this automatic behavior.
 func AddTool[In, Out any](s *Server, t *Tool, h ToolHandlerFor[In, Out]) {
 	tt, hh, err := toolForErr(t, h)
 	if err != nil {
 		panic(fmt.Sprintf("AddTool: tool %q: %v", t.Name, err))
 	}
-	s.AddTool(tt, hh)
+	s.AddRawTool(tt, hh)
 }
 
 // RemoveTools removes the tools with the given names.

mcp/server_test.go

@@ -299,7 +299,7 @@ func TestServerCapabilities(t *testing.T) {
 		{
 			name: "With tools",
 			configureServer: func(s *Server) {
-				s.AddTool(tool, nil)
+				s.AddRawTool(tool, nil)
 			},
 			wantCapabilities: &ServerCapabilities{
 				Logging: &LoggingCapabilities{},
@@ -325,7 +325,7 @@ func TestServerCapabilities(t *testing.T) {
 				s.AddPrompt(&Prompt{Name: "p"}, nil)
 				s.AddResource(&Resource{URI: "file:///r"}, nil)
 				s.AddResourceTemplate(&ResourceTemplate{URITemplate: "file:///rt"}, nil)
-				s.AddTool(tool, nil)
+				s.AddRawTool(tool, nil)
 			},
 			serverOpts: ServerOptions{
 				SubscribeHandler: func(context.Context, *SubscribeRequest) error {

mcp/streamable_test.go

@@ -837,7 +837,7 @@ func TestStreamableServerTransport(t *testing.T) {
 			// Create a server containing a single tool, which runs the test tool
 			// behavior, if any.
 			server := NewServer(&Implementation{Name: "testServer", Version: "v1.0.0"}, nil)
-			server.AddTool(
+			server.AddRawTool(
 				&Tool{Name: "tool", InputSchema: &jsonschema.Schema{Type: "object"}},
 				func(ctx context.Context, req *CallToolRequest) (*CallToolResult, error) {
 					if test.tool != nil {

mcp/tool.go

@@ -14,7 +14,7 @@ import (
 
 // A ToolHandler handles a call to tools/call.
 //
-// This is a low-level API, for use with [Server.AddTool]. It does not do any
+// This is a low-level API, for use with [Server.AddRawTool]. It does not do any
 // pre- or post-processing of the request or result: the params contain raw
 // arguments, no input validation is performed, and the result is returned to
 // the user as-is, without any validation of the output.