Sloot MCP Server

A complete TypeScript Model Context Protocol (MCP) server implementation using Express.js and the official MCP SDK.

Features

• 🚀 Express.js HTTP Server: RESTful API with MCP protocol support

• 🔧 Session Management: Automatic session handling with UUID-based session IDs

• 🛠️ Built-in Tools: Example tools including echo, time, and calculator

• 📡 Streamable Transport: HTTP-based transport with Server-Sent Events (SSE)

• 🔒 Type Safety: Full TypeScript implementation with strict typing

• ❤️ Health Monitoring: Built-in health check endpoint

Available Tools

The server provides the following MCP tools:

1. echo - Echo back any message

2. get_time - Get current server time

3. calculate - Perform basic mathematical calculations

Quick Start

Prerequisites

• Node.js 18+

• npm or yarn

Code Quality Tools

This project includes:

• ESLint - Code linting with TypeScript support

• Prettier - Code formatting

• TypeScript - Type checking and compilation

Installation

1. Clone or download this project

2. Install dependencies:

Development

Run the server in development mode with hot reload:

Production

Build and run the production server:

Watch Mode

Run with file watching for development:

Code Quality

Check code quality and formatting:

Usage

Starting the Server

The server will start on port 3000 by default (configurable via PORT environment variable):

MCP Endpoints

• POST /mcp - Main MCP communication endpoint

• GET /mcp - Server-to-client notifications (SSE)

• DELETE /mcp - Session termination

• GET /health - Health check and status

Testing the Server

You can test the health endpoint:

Response:

MCP Client Integration

This server is designed to work with MCP clients. The server handles:

• Session initialization with automatic UUID generation

• Session persistence across requests

• Proper cleanup when sessions are closed

• DNS rebinding protection (configurable)

Session Headers

When making requests to the MCP endpoint, include the session ID in headers:

Configuration

Environment Variables

• PORT - Server port (default: 3000)

DNS Rebinding Protection

For local development, you can enable DNS rebinding protection by uncommenting and configuring these options in the transport configuration:

Development

Project Structure

Scripts

• npm run build - Compile TypeScript to JavaScript

• npm run start - Run the compiled server

• npm run dev - Run with tsx for development

• npm run watch - Run with file watching

• npm run lint - Run ESLint to check for code issues

• npm run lint:fix - Run ESLint and automatically fix issues

• npm run format - Format code with Prettier

• npm run format:check - Check if code is properly formatted

• npm run check - Run linting, formatting check, and build

Extending the Server

Adding New Tools

To add new tools, modify the ListToolsRequestSchema handler in src/index.ts:

Then add the tool implementation in the CallToolRequestSchema handler.

Adding Resources

You can add MCP resources by implementing the appropriate request handlers for resources.

License

MIT