/add-error-handling

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🚨 EXECUTION NOTICE FOR CLAUDE

When you invoke this command via SlashCommand, the system returns THESE INSTRUCTIONS below.

YOU are the executor. This is NOT an autonomous subprocess.

• ✅ The phases below are YOUR execution checklist
• ✅ YOU must run each phase immediately using tools (Bash, Read, Write, Edit, TodoWrite)
• ✅ Complete ALL phases before considering this command done
• ❌ DON't wait for "the command to complete" - YOU complete it by executing the phases
• ❌ DON't treat this as status output - it IS your instruction set

Immediately after SlashCommand returns, start executing Phase 0, then Phase 1, etc.

See @CLAUDE.md section "SlashCommand Execution - YOU Are The Executor" for detailed explanation.

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Arguments: $ARGUMENTS

Goal: Add robust error handling, retry logic, and exception tracking to Celery tasks

Core Principles:

• Detect existing error handling patterns
• Configure exponential backoff retries
• Implement custom error handlers
• Add logging and monitoring

Phase 1: Discovery Goal: Understand current task implementation and error handling state

Actions:

• Parse $ARGUMENTS for task name/pattern
• Find existing Celery tasks:
  • !{bash find . -type f -name ".py" -path "/tasks/*" 2>/dev/null | head -20}
• Detect current error handling approaches
• Load project configuration for Celery settings

Phase 2: Analysis Goal: Identify error-prone operations and retry requirements

Actions:

• Read identified task files to understand:
  • Current retry decorators
  • Exception handling blocks
  • Logging patterns
  • External API calls or database operations
• Check for existing Celery configuration:
  • !{bash grep -r "CELERY_" . --include="*.py" --include="settings.py" | head -10}

Phase 3: Implementation Goal: Add comprehensive error handling via task-generator-agent

Actions:

Task(description="Implement error handling and retries", subagent_type="celery:task-generator-agent", prompt="You are the task-generator-agent. Implement comprehensive error handling and retry strategies for $ARGUMENTS.

Context:

• Task files and patterns identified in discovery
• Existing error handling approaches
• Project Celery configuration

Requirements:

• Add retry decorators with exponential backoff
• Implement custom exception handlers for specific errors
• Add structured logging for debugging
• Configure max_retries and retry_backoff parameters
• Add error callbacks for final failure handling
• Use autoretry_for for known transient errors
• Implement custom on_failure handlers
• Add error tracking integration (Sentry if available)

Error Handling Patterns:

1. Network/API errors - Retry with backoff
2. Database errors - Short retry with circuit breaker
3. Business logic errors - No retry, log and alert
4. Validation errors - No retry, immediate failure
5. Resource exhaustion - Exponential backoff

Expected Output:

• Updated task files with retry decorators
• Custom exception classes if needed
• Error handler implementations
• Celery configuration updates
• Logging configuration
• Documentation of error handling strategy")

Phase 4: Validation Goal: Verify error handling implementation

Actions:

• Check updated task files for proper decorators
• Verify retry configuration is present
• Ensure exception handlers are implemented
• Validate logging is configured
• Run syntax check: !{bash python -m py_compile $(find . -name "tasks.py" 2>/dev/null) 2>&1 | head -20}

Phase 5: Summary Goal: Document error handling implementation

Actions:

• List tasks updated with error handling
• Summarize retry strategies configured
• Document exception types handled
• Show error tracking integration
• Provide testing recommendations