Error Handling Skill

Comprehensive, layered error handling for Next.js applications. This file holds the architecture and contract; copy-paste code is in the references.

• references/patterns.md — error-handling patterns by layer.
• references/examples.md — full worked examples (complete CRUD with errors).
• references/retry-patterns.md — retry, circuit breaker, resilience.
• references/validation-vs-runtime.md — validation vs runtime errors.

Philosophy

1. Never expose internal errors to users — log details server-side, show friendly messages client-side.
2. Use typed errors — ServiceError for any service layer, ActionResponse for server actions.
3. Fail gracefully — error boundaries, fallback UI, retry mechanisms.
4. Log everything — structured logging with context before returning an error.
5. Provide feedback — toast notifications for user-facing errors.

The Four Layers