Exploration

A simple TypeScript MCP (Model Context Protocol) server using @modelcontextprotocol/sdk.

Overview

This project demonstrates how to create a basic MCP server with tools that can be accessed by MCP clients like Claude Desktop, VS Code with GitHub Copilot, or other MCP-compatible applications.

Features

• Calculator Tool: Performs basic arithmetic operations (add, subtract, multiply, divide)

Installation

pnpm install

Development

Run the server in development mode:

pnpm dev

Build

Compile TypeScript to JavaScript:

pnpm build

Run

Start the compiled server:

pnpm start

The server will start on http://localhost:3000/mcp.

Connecting to the Server

Using VS Code

Add this to your MCP configuration in VS Code:

{
  "mcpServers": {
    "simple-mcp-server": {
      "url": "http://localhost:3000/mcp",
      "type": "http"
    }
  }
}

Using MCPJam

Test your server with the MCPJam:

pnpx @mcpjam/inspector@latest --port 4000

Then create a new server with your MCP url.

Available Tools

calculate

Performs basic arithmetic operations.

Parameters:

• operation (enum): One of "add", "subtract", "multiply", "divide"
• a (number): First number
• b (number): Second number

Example:

{
  "operation": "add",
  "a": 5,
  "b": 3
}

Architecture

This server uses:

• Express.js for HTTP server functionality
• @modelcontextprotocol/sdk for MCP protocol implementation
• Zod for schema validation
• Streamable HTTP Transport for stateless request handling

Learn More

• Model Context Protocol Documentation
• TypeScript SDK Documentation
• MCP Specification