review-error-handling_skill

Overview

This skill performs error handling and resilience-focused code reviews to surface gaps in exception management, recovery strategies, and resource cleanup. It highlights critical risks like unhandled exceptions, silent failures, and missing timeouts, and recommends concrete fixes. Use it to improve system robustness, observability, and user-facing behavior under failure conditions.

How this skill works

The review inspects exception handling, error propagation, retry and recovery patterns, graceful degradation, and resource cleanup paths. It checks for specific catch blocks, preserved error context, meaningful error types, backoff and retry limits, idempotency, fallbacks, timeouts, and cleanup in failure flows. Results are categorized by severity and include actionable findings and remediation suggestions.

When to use it

• When validating exception handling before a release or after an incident
• When adding retries, circuit breakers, or fallback logic to external calls
• When auditing error propagation across service boundaries or libraries
• When implementing transactional or cleanup logic that must run on failure
• When improving user-facing error messages and degraded-mode behavior

Best practices

• Catch specific exceptions and avoid bare catch-all blocks unless justified
• Preserve and enrich error context when rethrowing to aid debugging
• Use structured error types or Result/Either patterns rather than generic strings
• Implement idempotency for retried operations and configure exponential backoff and max retries
• Set timeouts on external calls and provide safe, documented fallbacks
• Ensure finally/defer/cleanup paths always release resources and roll back transactions

Example use cases

• Review a service change that adds external API retries to ensure idempotency and backoff
• Audit database transaction handling to confirm rollbacks and resource cleanup on failures
• Validate that user-facing errors do not leak sensitive details and provide useful next steps
• Assess a new circuit breaker implementation and its integration with retry logic
• Check batch processing code for partial failure handling and retry/fallback strategies