Function mcpFromSDK

cli/exp_mcp.go:988–1026

mcpFromSDK adapts a toolsdk.Tool to go-mcp's server.ServerTool. It assumes that the tool responds with a valid JSON object.

(sdkTool toolsdk.GenericTool, tb toolsdk.Deps)

// mcpFromSDK adapts a toolsdk.Tool to go-mcp's server.ServerTool.
// It assumes that the tool responds with a valid JSON object.
func mcpFromSDK(sdkTool toolsdk.GenericTool, tb toolsdk.Deps) server.ServerTool {
	// NOTE: some clients will silently refuse to use tools if there is an issue
	// with the tool's schema or configuration.
	if sdkTool.Schema.Properties == nil {
		panic("developer error: schema properties cannot be nil")
	}
	return server.ServerTool{
		Tool: mcp.Tool{
			Name:        sdkTool.Tool.Name,
			Description: sdkTool.Description,
			InputSchema: mcp.ToolInputSchema{
				Type:       "object", // Default of mcp.NewTool()
				Properties: sdkTool.Schema.Properties,
				Required:   sdkTool.Schema.Required,
			},
			Annotations: mcp.ToolAnnotation{
				ReadOnlyHint:    mcp.ToBoolPtr(sdkTool.MCPAnnotations.ReadOnlyHint),
				DestructiveHint: mcp.ToBoolPtr(sdkTool.MCPAnnotations.DestructiveHint),
				IdempotentHint:  mcp.ToBoolPtr(sdkTool.MCPAnnotations.IdempotentHint),
				OpenWorldHint:   mcp.ToBoolPtr(sdkTool.MCPAnnotations.OpenWorldHint),
			},
		},
		Handler: func(ctx context.Context, request mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			var buf bytes.Buffer
			if err := json.NewEncoder(&buf).Encode(request.Params.Arguments); err != nil {
				return nil, xerrors.Errorf("failed to encode request arguments: %w", err)
			}
			result, err := sdkTool.Handler(ctx, tb, buf.Bytes())
			if err != nil {
				return nil, err
			}
			return &mcp.CallToolResult{
				Content: []mcp.Content{
					mcp.NewTextContent(string(result)),
				},
			}, nil
		},
	}
}