MCP Server

The MCP Server plugin allows you to expose your Shokupan application’s endpoints as tools to Large Language Models (LLMs) via the Model Context Protocol.

Features

• Automatic Tool Registration: Automatically converts your OpenAPI endpoints (GET, POST, etc.) into MCP tools.
• Introspection: Supports MCP introspection for discovering available tools.
• SSE Transport: Uses Server-Sent Events (SSE) for communication with MCP clients.
• Configurable: Control which tools are exposed and how they behave.

Installation

The MCP Server plugin is included in the shokupan package.

import { Shokupan, McpServerPlugin } from 'shokupan';

const app = new Shokupan({
    enableOpenApiGen: true // Required: Tools are generated from OpenAPI spec
});

// Register the MCP server
app.register(new McpServerPlugin({
    path: '/mcp', // Mount path for SSE endpoint
    allowIntrospection: true,
    allowToolExecution: true
}));

Configuration

The McpServerPlugin accepts the following options:

interface McpServerPluginOptions { /** * Path to mount the MCP server (SSE endpoint). * @default ‘/mcp’ */ path?: string;

/**
 * Root directory to scan for OpenAPI documents.
 * @default process.cwd()
 */
rootDir?: string;

/**
 * Whether to allow introspection (listing tools).
 * @default true
 */
allowIntrospection?: boolean;

/**
 * Whether to allow tool execution.
 * @default true
 */
allowToolExecution?: boolean;

}

## Available Prompts

The server exposes several built-in prompts for LLMs:

- `generate-client`: Generates a TypeScript client for an endpoint.
- `refactor-endpoint`: Suggests refactoring improvements for an endpoint handler.
- `generate-tests`: specific unit tests for an endpoint.

## How It Works

The plugin analyzes your application's generated OpenAPI specification. Each operation (endpoint) in the spec is registered as an MCP tool.

- **Tool Name**: Derived from the operation ID or method + path (e.g., `get_users`).
- **Description**: Taken from the operation summary or description.
- **Arguments**: The tool's input schema is derived from the endpoint's request body and parameters.

When an MCP client (like an LLM agent) calls a tool, the plugin internally routes the request to the corresponding Shokupan handler, executing it as if it were a standard HTTP request.