Weather MCP Server

A Model Context Protocol server exposing a single get-weather tool. An MCP client — Claude Desktop, or any agent that speaks MCP — calls the tool with a city name and gets the current temperature back.

Built on the official TypeScript SDK, communicating over stdio, with tool input validated by Zod.

The tool

Name	get-weather
Input	{ "city": string }
Output	Current temperature in Istanbul: 21.3°C
Upstream	WeatherAPI.com current.json

Failed upstream requests and unknown tool names come back as plain text content rather than protocol errors, so the calling model can recover instead of losing the turn.

Requirements

• Node.js 22
• A free API key from weatherapi.com

Setup

npm install
npm run build

Two environment variables are required:

Variable	Value
WEATHER_API_BASE_URL	https://api.weatherapi.com/v1/current.json
WEATHER_API_KEY	your WeatherAPI key

Running it

WEATHER_API_BASE_URL=https://api.weatherapi.com/v1/current.json \
WEATHER_API_KEY=your_key \
node dist/index.js

The server talks MCP over stdio, so it prints nothing on its own — it waits for a client to connect. Running it by hand is only useful to check that it starts without crashing.

Connecting it to Claude Desktop

Add the server to claude_desktop_config.json:

• macOS — ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows — %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "weather": {
      "command": "node",
      "args": ["/absolute/path/to/getWeather-MCPServer/dist/index.js"],
      "env": {
        "WEATHER_API_BASE_URL": "https://api.weatherapi.com/v1/current.json",
        "WEATHER_API_KEY": "your_key"
      }
    }
  }
}

Run npm run build first — the config points at the compiled output, not the TypeScript source. Then restart Claude Desktop. The tool appears under the connector icon, and asking "what is the temperature in Izmir?" triggers a get-weather call.

Project layout

src/index.ts    the whole server — tool listing, tool body, stdio transport
tsconfig.json   compiles src/ to dist/ as ESNext / NodeNext modules

License

MIT