mcp-basic

README

MCP Basic Example

A simple example demonstrating the MCP extension with automatic route-to-tool conversion.

Features

• Auto-exposes REST routes as MCP tools
• Simple CRUD operations for users
• Tool naming with prefix
• Pattern-based route filtering

Running

cd v2/examples/mcp-basic
go run main.go

Testing

List all available tools

curl http://localhost:8080/_/mcp/tools | jq

Expected output shows tools like:

• example_get_users
• example_get_users_id
• example_create_users
• example_update_users_id
• example_delete_users_id

Get user by ID

curl -X POST http://localhost:8080/_/mcp/tools/example_get_users_id \
  -H "Content-Type: application/json" \
  -d '{
    "name": "example_get_users_id",
    "arguments": {
      "id": "1"
    }
  }' | jq

Create a new user

curl -X POST http://localhost:8080/_/mcp/tools/example_create_users \
  -H "Content-Type: application/json" \
  -d '{
    "name": "example_create_users",
    "arguments": {
      "body": {
        "name": "Charlie",
        "email": "charlie@example.com"
      }
    }
  }' | jq

List all users

curl -X POST http://localhost:8080/_/mcp/tools/example_get_users \
  -H "Content-Type: application/json" \
  -d '{
    "name": "example_get_users",
    "arguments": {}
  }' | jq

What's Happening

1. Route Registration: The app registers standard REST routes (GET /users, POST /users, etc.)
2. Auto-Exposure: MCP extension automatically converts these routes to tools
3. Tool Naming: Routes become tools with names like example_get_users_id
4. Schema Generation: Input schemas are auto-generated from route metadata
5. Execution: Calling a tool executes the underlying HTTP route

Key Concepts

• Tool Prefix: All tools have example_ prefix for namespace
• Pattern Exclusion: /_/* routes (like MCP endpoints) are excluded
• Path Parameters: :id in /users/:id becomes required id argument
• Request Body: POST/PUT methods accept body argument
• Query Parameters: Optional query argument for query strings