MCP-Server

A minimal Model Context Protocol (MCP) server built with TypeScript. It exposes a single tool, get_weather, over a stdio transport so that MCP-compatible clients (Claude Desktop, Claude Code, the MCP Inspector, etc.) can call it.

Features

• Built on @modelcontextprotocol/sdk

• Input validation via zod

• Communicates over stdio (JSON-RPC)

• One example tool: get_weather

Related MCP server: MCP Demo Server

Prerequisites

• Node.js (v18+ recommended)

• Yarn (v1 classic or Berry)

Installation

yarn install

Build

Compiles the TypeScript source in src/ to JavaScript in build/:

yarn build

This runs tsc and marks build/index.js as executable.

Running

Start the server directly (for a quick smoke test — it will sit silently listening on stdio, which is expected):

yarn start

Start with the MCP Inspector (recommended for interactive testing/debugging):

yarn start:local

This launches a local web UI (usually at http://localhost:6274) where you can view the registered tools, call them with test inputs, and inspect the raw JSON-RPC traffic.

If running the Inspector through a Yarn script causes connection issues, run it directly instead:

npx @modelcontextprotocol/inspector node build/index.js

Available Tools

get_weather

Returns a (currently mocked) weather reading for a given city.

Input:

Example output:

The weather in Chandigarh is 24°C and sunny.

Note: this is a stub implementation returning a random temperature. Replace the logic inside registerTool("get_weather", ...) in src/index.ts with a real weather API call as needed.

Connecting to an MCP Client

To use this server with Claude Desktop or another MCP client, add it to the client's config (e.g. claude_desktop_config.json):

{
  "mcpServers": {
    "MCP-Server": {
      "command": "node",
      "args": ["/absolute/path/to/MCP-Server/build/index.js"]
    }
  }
}

Restart the client afterward — the get_weather tool should appear as available.

Project Structure

.
├── src/
│   └── index.ts        # Server entry point + tool definitions
├── build/               # Compiled output (generated by `yarn build`)
├── package.json
├── tsconfig.json
└── README.md

Extending

To add more tools, call server.registerTool(...) again inside src/index.ts with a new name, schema, and handler. For larger projects, consider splitting each tool into its own file under src/tools/ and importing them into index.ts.

License

MIT