Clerk auth with API Keys beta (Dec 2025), Next.js 16 proxy.ts (March 2025 CVE context), API version 2025-11-10 breaking changes, clerkMiddleware() options, webhooks, production considerations (GCP outages), and component reference. Prevents 15 documented errors. Use when: API keys for users/orgs, Next.js 16 middleware filename, troubleshooting JWKS/CSRF/JWT/token-type-mismatch errors, webhook verification, user type inconsistencies, or testing with 424242 OTP.