error-handling

SKILL.md

Error Handling Patterns

Consistent, robust error handling patterns for production applications.

When to Activate

Designing error types or exception hierarchies for a new module or service

Adding retry logic or circuit breakers for unreliable external dependencies

Reviewing API endpoints for missing error handling

Implementing user-facing error messages and feedback

Debugging cascading failures or silent error swallowing

Core Principles

Fail fast and loudly — surface errors at the boundary where they occur; don't bury them

Typed errors over string messages — errors are first-class values with structure

User messages ≠ developer messages — show friendly text to users, log full context server-side

Never swallow errors silently — every catch block must either handle, re-throw, or log

Errors are part of your API contract — document every error code a client may receive