skill:clerk-auth - Clerk Authentication Integration

Version: 1.0.0

Purpose

Implements Clerk authentication integration for Next.js applications using @clerk/nextjs. This skill covers the full Clerk auth lifecycle: clerkMiddleware() configuration, API Keys beta (Dec 2025), Next.js 16 proxy.ts (March 2025 CVE context), API version 2025-11-10 breaking changes, webhook handlers with svix verification, and production deployment considerations.

Use this skill when:

• Setting up Clerk authentication in a Next.js project (App Router or Pages Router)
• Configuring clerkMiddleware() with route protection and public routes
• Enabling API Keys beta for machine-to-machine authentication
• Setting up proxy.ts for Next.js 16 satellite domain requirements
• Implementing Clerk webhook handlers with svix signature verification
• Migrating to API version 2025-11-10 breaking changes
• Resolving common Clerk auth errors and misconfigurations