# MCP-Server

A minimal [Model Context Protocol](https://modelcontextprotocol.io) (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`

## Prerequisites

- Node.js (v18+ recommended)
- Yarn (v1 classic or Berry)

## Installation

```bash
yarn install
```

## Build

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

```bash
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):

```bash
yarn start
```

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

```bash
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:
> ```bash
> npx @modelcontextprotocol/inspector node build/index.js
> ```

## Available Tools

### `get_weather`

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

**Input:**

| Parameter | Type   | Description       |
|-----------|--------|--------------------|
| `city`    | string | Name of the city   |

**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`):

```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