Securing AI Agents with Auth0: Complete MCP Server Implementation

This is a submission for the Auth0 for AI Agents Challenge

What I Built

I built Auth XMCP - Next.js, a secure Next.js application that provides OAuth-protected Model Context Protocol (MCP) endpoints using Auth0 authentication. This project demonstrates how to build a modern MCP server with enterprise-grade security and Next.js integration.

The application solves a critical problem in the AI ecosystem: secure communication between AI agents and external systems. As AI agents become more prevalent, they need secure ways to access resources, tools, and data. My solution provides:

• 🔐 OAuth Authentication: Secure MCP endpoints with Auth0 integration
• 🚀 Full MCP Server: Complete Model Context Protocol server with tools, resources, and prompts
• ⚡ Next.js 15: Built with the latest Next.js features including Turbopack
• 🛡️ JWT Verification: Robust token validation with JWKS support
• 🎨 Modern UI: Clean interface with TailwindCSS and dark mode support

Demo

https://github.com/uratmangun/auth-xmcp-nextjs/tree/auth0

https://auth-xmcp-nextjs.vercel.app

Technology Stack:

• Next.js 15.5.2 with React 19.2.0
• TypeScript 5.9.3 with full type safety
• Auth0 NextJS SDK 4.10.0
• XMCP 0.3.2 with Next.js adapter
• TailwindCSS 4.1.14, Zod 3.24.4, jose 5.10.0

Key Features:

1. Secure MCP endpoint at /mcp requiring Auth0 JWT tokens
2. AI agent authentication flow via Auth0
3. MCP tools with parameter validation
4. Configuration and user resources
5. Code review prompts

How I Used Auth0 for AI Agents

Auth0 secures my MCP server through:

🔐 JWT Token Validation

• Tokens verified against Auth0's JWKS
• Claims validation for issuer and audience
• Automatic middleware protection

🚀 OAuth Flow Integration

• Client credentials flow for AI agents
• Scoped tokens for MCP operations
• Automatic token refresh

🛡️ Enterprise Security

• RBAC for different agent permissions
• Audit logging and rate limiting
• Multi-factor authentication support

Lessons Learned and Takeaways

Key Challenges:

1. JWT integration with XMCP framework required careful middleware design
2. Ensuring end-to-end TypeScript safety
3. Working with bleeding-edge Next.js 15 features

Technical Insights:

• AI agents need robust authentication from day one
• Zod schemas prevent runtime errors in production
• Next.js 15 + Turbopack provides excellent developer experience
• Auth0's JWKS simplifies key rotation and certificate management

Advice for Developers:

1. Start with security - don't treat authentication as an afterthought
2. Use type safety with Zod + TypeScript
3. Leverage modern tools: Next.js 15, XMCP, and Auth0 work beautifully together
4. Test thoroughly - AI agent authentication requires comprehensive testing
5. Document everything for better integration

This project demonstrates that building secure, production-ready AI agent infrastructure is achievable with the right tools. The combination of Auth0 and MCP opens exciting possibilities for secure AI ecosystems.

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Built with ❤️ using Next.js, XMCP, and Auth0