error-handling

name	error-handling
description	Implements error handling patterns, structured logging, retry strategies, circuit breakers, and graceful degradation. Use when designing error handling, setting up logging, implementing retries, adding error tracking, or when asked about error boundaries, log aggregation, alerting, or resilience patterns.

Error Handling & Observability

When to Load

• Trigger: Try/catch patterns, retry logic, error responses, circuit breakers, structured logging
• Skip: No error handling or observability involved in the current task

Error Handling Workflow

Copy this checklist and track progress:

Error Handling Progress:
- [ ] Step 1: Define error taxonomy (categories and severity)
- [ ] Step 2: Implement error handling by layer
- [ ] Step 3: Set up structured logging
- [ ] Step 4: Add retry and circuit breaker patterns
- [ ] Step 5: Configure error tracking service
- [ ] Step 6: Define user-facing error messages
- [ ] Step 7: Validate against anti-patterns checklist

Error Handling Patterns by Language

JavaScript / TypeScript

// Custom error hierarchy
class AppError extends Error {
  constructor(
    message: string,
    public statusCode: number = 500,
    public code: string = ,
     :  = ,
  ) {
    (message);
    . = ..;
  }
}
    {
  () {
    (, , );
  }
}
    {
  () {
    (, , );
  }
}


 {
   (data);
}  (e) {
  
}


 {
   (data);
}  (e) {
   e; 
}


 {
   (data);
}  (error) {
   (error  ) {
     res.().({ : error. });
  }
  logger.(, { error, : data. });
    (, , );
}