> ## Documentation Index
> Fetch the complete documentation index at: https://docs.grantex.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# MCP Auth Server

> Drop-in OAuth 2.1 + PKCE authorization server for any MCP server. Powered by Grantex.

<Info>Full feature guide: [MCP Auth Server](/features/mcp-auth-server)</Info>

## Overview

`@grantex/mcp-auth` is a production-ready OAuth 2.1 + PKCE authorization server that adds delegated auth to any MCP (Model Context Protocol) server. Works with Claude Desktop, Cursor, Windsurf, and any MCP-compatible client.

## Install

```bash theme={null}
npm install @grantex/mcp-auth
```

## Quick Start

```typescript theme={null}
import { createMcpAuthServer } from '@grantex/mcp-auth';

const auth = createMcpAuthServer({
  grantexApiKey: process.env.GRANTEX_API_KEY!,
  issuer: 'https://auth.myapp.com',
  scopes: ['calendar:read', 'email:send'],
});

// Mount on Express
app.use('/oauth', auth.routes());
```

### What You Get

* **OAuth 2.1 + PKCE** — authorization code flow with S256 challenge
* **Client registration** — dynamic or pre-registered MCP clients
* **Token introspection** — validate tokens issued by this server
* **Token revocation** — revoke access at any time
* **Grantex-backed** — tokens are Grantex grant tokens with full audit trail

## Links

* [Full Feature Guide](/features/mcp-auth-server)
* [npm: @grantex/mcp-auth](https://npmjs.com/package/@grantex/mcp-auth)