The Hello World MCP Server demonstrates a minimal MCP implementation using the MCP SDK with Express to expose endpoints for server-sent events (SSE) and message handling. It registers a set of MCP tools and prompts that allow clients to interact with the server, inspect its capabilities, and send messages or queries through the configured endpoints. You can use the MCP Inspector to quickly test and verify that the server’s tools and prompts are wired up correctly, ensuring that the server responds as expected to prompts, tool invocations, and SSE streams.

To operate the server, run it and connect with the MCP ecosystem as described in the project blog. The server exposes HTTP endpoints via Express for SSE streams and message exchange, enabling clients to subscribe to event streams, send messages, and receive structured responses generated by the server’s tools and prompts. The included inspector tooling helps you validate tool registrations and prompt configurations in an interactive way.

Prerequisites:

• Node.js v16 or higher
• npm (comes with Node.js) or yarn

Step-by-step installation:

1. Clone the repository: git clone https://github.com/your-username/hello-world-mcp-server.git cd hello-world-mcp-server

2. Install dependencies: npm install

   or if you prefer yarn

   yarn install

3. Configure environment:

   • Copy the example environment file and adjust as needed: cp .env.example .env
   • Edit .env to set PORT (default 4000).

4. Build the project (TypeScript to JavaScript): npm run build

   or

   yarn build

5. Run the server: npm start

   or for development with live reload

   npm run dev

Environment and configuration tips:

• The server reads configuration from a .env file. Common variables include PORT to expose the HTTP server. If PORT is in use, change it in .env.
• If you encounter TypeScript errors after pulling changes, ensure dependencies are installed and run a clean build (delete dist if necessary and reinstall).
• The MCP Inspector command (npx @modelcontextprotocol/inspector ./dist/server.js) can help you verify registered tools and prompts.
• Ensure your Node.js version matches the project’s expected range (v16+). If using npm, npm ci can help lock down dependencies for CI environments.

Common issues:

• Port already in use: update PORT in .env and restart.
• Build failures: verify TypeScript config (tsconfig.json) and that dependencies install correctly.