middy-mcp

# Middy MCP A Middy middleware for Model Context Protocol (MCP) server integration with AWS Lambda functions. ## Description Middy MCP is a middleware that enables seamless integration between AWS Lambda functions and Model Context Protocol servers. It provides a convenient way to handle MCP requests and responses within your Lambda functions using the Middy middleware framework. It supports requests sent to AWS Lambda from API Gateway (both REST API / v1 and HTTP API / v2) using the Proxy integration, as well as requests sent form an ALB. > Disclaimer: hosting your MCP server this way is only compatible with MCP clients using at least protocol version 2025-03-26. ## Install ```bash pnpm install middy-mcp ``` ## Requirements - Node.js >= 18.0.0 - Middy >= 6.0.0 ## Usage This middleware can throw HTTP exceptions, so it can be convenient to use it in combination with the `@middy/http-error-handler`. Hereafter is an exemple of a minimal Lambda function handler file. Deploy this lambda as a proxy integration on a `POST` route of your API Gateway and you're good to go. ```typescript import middy from "@middy/core"; import httpErrorHandler from "@middy/http-error-handler"; import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js"; import { z } from "zod"; import mcpMiddleware from "middy-mcp"; // Create an MCP server const server = new McpServer({ name: "Lambda hosted MCP Server", version: "1.0.0", }); // Add an addition tool server.tool("add", { a: z.number(), b: z.number() }, async ({ a, b }) => ({ content: [{ type: "text", text: String(a + b) }], })); export const handler = middy() .use(mcpMiddleware({ server })) .use(httpErrorHandler()); ``` ## License This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details. ## Contributing Contributions are welcome! Please feel free to open an issue or to submit a pull request 🚀!