Systematic Debugging

When to Use

Invoke this methodology automatically when:

• A test fails and the cause isn't immediately obvious
• Unexpected behavior occurs in production or development
• An error message doesn't directly point to the fix
• Multiple potential causes exist

Core Principles

1. Hypothesize before acting - Form explicit hypotheses about root cause before changing code
2. Test hypotheses systematically - Validate or eliminate each hypothesis with evidence
3. Parallelize investigation - Use subagents for concurrent readonly exploration
4. Preserve test integrity - Never weaken tests to make them pass

Debugging Scope Ladder