🔐 auth-setup — MCP Server

auth setup is a custom Model Context Protocol (MCP) server that helps developers set up authentication in a Next.js application through an interactive, adapter-aware flow.

Instead of copy-pasting auth docs, developers answer a few guided questions and get a fully configured authentication system tailored to their stack.

✨ What This MCP Server Does

• Guides authentication setup for Next.js (App Router first)
• Supports multiple authentication libraries
• Asks only relevant questions based on the selected auth library
• Automatically configures:
  • Adapters (ORM / database)
  • Providers
  • API routes
  • Helpers
  • Environment variables
• Outputs production-ready auth code

🔧 Supported Authentication Libraries

The MCP server is library-agnostic and currently supports:

• Auth.js (v5)
• Better Auth

Designed to be easily extended to Clerk, Lucia, Supabase Auth, custom auth, etc.

🧠 How It Works

Interactive Tool Flow

When the MCP server runs, it exposes tools that AI agents can call:

1. check_nextjs_project - Validates if a directory is a Next.js project with App Router
2. setup_nextjs_auth - Sets up authentication with the specified library and configuration

The AI agent can:

1. Detect or ask for the authentication library
2. Ask library-specific questions, such as:
   • Which database or ORM adapter are you using?
     • Prisma
     • Drizzle
     • None (JWT / hosted auth)
3. Skip unnecessary prompts automatically

🔌 MCP Integration

Add this server to your MCP client (like Warp):

CLI Server (Command) Configuration

{
  "auth-setup": {
    "command": "npx",
    "args": ["-y", "auth-setup"]
  }
}

Or with a local installation:

{
  "auth-setup": {
    "command": "node",
    "args": ["/path/to/auth-setup/dist/mcp-server.js"]
  }
}

🛠️ Available Tools

setup_nextjs_auth

Set up authentication in a Next.js application.

Parameters:

• projectPath (string, required): Absolute path to the Next.js project
• authLibrary (string, required): "authjs" or "better-auth"
• providers (array, optional): OAuth providers like ["google", "github", "credentials"] (Auth.js only)
• adapter (string, optional): Database adapter: "prisma", "drizzle", or "none"

Example:

{
  "projectPath": "/home/user/my-nextjs-app",
  "authLibrary": "authjs",
  "providers": ["google", "github"],
  "adapter": "prisma"
}

check_nextjs_project

Verify if a directory is a valid Next.js project.

Parameters:

• projectPath (string, required): Path to check

Returns:

{
  "isNextJs": true,
  "hasAppRouter": true,
  "valid": true,
  "message": "Valid Next.js project with App Router"
}

📁 Generated Output (Example)

After running setup_nextjs_auth:

{
  "success": true,
  "authLibrary": "authjs",
  "providers": ["google", "github"],
  "adapter": "prisma",
  "filesCreated": [
    "auth.ts",
    "middleware.ts",
    "app/api/auth/[...nextauth]/route.ts",
    "app/auth/signin/page.tsx",
    ".env.local"
  ],
  "nextSteps": [
    "Run: npm install",
    "Update .env.local with OAuth credentials",
    "Generate auth secret: openssl rand -base64 32"
  ]
}

🧩 Design Principles

• Interactive, not verbose
• Adapter-aware
• Library-agnostic core
• Next.js App Router first
• Minimal developer effort
• Zero copy-paste boilerplate

🚀 Developer Experience with AI Agents

In Warp or other MCP clients, developers can simply ask:

"Set up Auth.js authentication with Google and GitHub in my Next.js project at /home/user/my-app"

The AI agent will:

1. Validate the project
2. Call the setup tool
3. Generate all necessary files
4. Provide next steps

No guessing. No broken tutorials.

🛣️ Roadmap

Planned extensions:

• Clerk Auth support
• Lucia Auth
• Supabase Auth
• Role & permission scaffolding
• Multi-tenant auth
• OAuth provider auto-setup

📦 Installation

As MCP Server (Recommended)

Add to your MCP client configuration (see MCP Integration above).

As CLI Tool

npx auth-setup init

🔧 Development

Building

npm install
npm run build

Testing Locally

node dist/mcp-server.js

📜 License

MIT

🤝 Contributing

Contributions welcome! Please see CONTRIBUTING.md for guidelines.

🆘 Support

• GitHub Issues for bugs
• GitHub Discussions for questions
• MCP Registry for discoverability

Built for the Next.js and MCP community 🚀