# xmcp Application

This project was created with [create-xmcp-app](https://github.com/basementstudio/xmcp).

[![Built with Copilot](https://img.shields.io/badge/-Built%20with%20Copilot-0d1117?style=flat&logo=githubcopilot&logoColor=ffffff)](https://github.com/features/copilot)

## Getting Started

First, run the development server:

```bash
npm run dev
# or
yarn dev
# or
pnpm dev
```

This will start the MCP server with the selected transport method.

## Project Structure

This project uses the structured approach where tools are automatically discovered from the `src/tools` directory. Each tool is defined in its own file with the following structure:

```typescript
import { z } from "zod";
import { type InferSchema } from "xmcp";

// Define the schema for tool parameters
export const schema = {
  a: z.number().describe("First number to add"),
  b: z.number().describe("Second number to add"),
};

// Define tool metadata
export const metadata = {
  name: "add",
  description: "Add two numbers together",
  annotations: {
    title: "Add Two Numbers",
    readOnlyHint: true,
    destructiveHint: false,
    idempotentHint: true,
  },
};

// Tool implementation
export default async function add({ a, b }: InferSchema<typeof schema>) {
  return {
    content: [{ type: "text", text: String(a + b) }],
  };
}
```

## Adding New Tools

To add a new tool:

1. Create a new `.ts` file in the `src/tools` directory
2. Export a `schema` object defining the tool parameters using Zod
3. Export a `metadata` object with tool information
4. Export a default function that implements the tool logic

## Building for Production

To build your project for production:

```bash
npm run build
# or
yarn build
# or
pnpm build
```

This will compile your TypeScript code and output it to the `dist` directory.

## Running the Server

You can run the server for the transport built with:

- HTTP: `node dist/http.js`
- STDIO: `node dist/stdio.js`

Given the selected transport method, you will have a custom start script added to the `package.json` file.

For HTTP:

```bash
npm run start-http
# or
yarn start-http
# or
pnpm start-http
```

For STDIO:

```bash
npm run start-stdio
# or
yarn start-stdio
# or
pnpm start-stdio
```

## Authentication

All requests to the MCP server must include an API key in the `x-api-key` header. You can set your API key in the `.env` file using the `YOUTUBE_MCP_API_KEY` variable.

Example:

```
YOUTUBE_MCP_API_KEY=your-secret-key
```

Requests without a valid API key will be rejected with a 401 error and a friendly message.

**How to use:**

```
curl -H "x-api-key: your-secret-key" http://localhost:3002/mcp
```

## Learn More

- [xmcp Documentation](https://xmcp.dev/docs)