Serverless MCP Server

🚀 Serverless MCP Server

A very simple Model Context Protocol (MCP) server deployed on AWS Lambda and exposed via Amazon API Gateway, using the Serverless Framework for deployment.

This framework is based on the outstanding work of Frédéric Barthelet. He developed a middy middleware to integrate the Model Context Protocol (MCP) server with AWS Lambda functions. The specific implementation can be found in this repository.

Long Story

📖Read the full article here

✨ Features

• 🪄 Minimal MCP server setup using @modelcontextprotocol/sdk.
• 🚀 Deployed as a single AWS Lambda function.
• 🌐 Exposed via an HTTP POST interface at the /mcp endpoint through API Gateway.
• 🔄 Supports local development using serverless-offline.
• 🧪 Includes a simple example tool (addition) and JSON-RPC interaction.

📦 Project Structure

serverless-mcp-server/
├── src/                    # Source code directory
│   └── index.js                # MCP server handler
├── .gitignore              # Git ignore file
├── package.json            # Project dependencies
├── package-lock.json       # Project lock file
├── README.md               # This documentation file
└── serverless.yml          # Serverless Framework configuration

🛠 Prerequisites

• Node.js v22+
• Open Source Serverless or Serverless Framework v3+
• Serverless Offline

🚀 Quick Start

Install Dependencies

npm install

Start the Local Server

sls local start

Visit http://localhost:3000 to view the documentation.

Deploy to AWS

sls deploy

After deployment, the console will output the URL of your MCP service.

📡 Deployment to AWS

Simply run:

sls deploy

After deployment, the MCP server will be available at the URL output in the console.

💻 Usage Examples

Basic Usage

In src/index.js, a simple "addition" tool is defined:

server.tool("add", { a: z.number(), b: z.number() }, async ({ a, b }) => ({
  content: [{ type: "text", text: String(a + b) }],
}));

Request Example

{
  "tool": "add",
  "args": {
    "a": 1,
    "b": 2
  }
}

Response Example

{
  "content": [
    { "type": "text", "text": "3" }
  ]
}

📄 License

MIT — You are free to fork, modify, and deploy your own version!