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name: systematic-debugging description: "[Debug] Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes - four-phase framework (root cause investigation, pattern analysis, hypothesis testing, implementation) that ensures understanding before attempting solutions. (project)"

Systematic Debugging

The Iron Law

CopyNO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST

The Four Phases

Phase 1: Root Cause Investigation

1. Read Error Messages Carefully
2. Reproduce Consistently
3. Check Recent Changes
4. Gather Evidence in Multi-Component Systems
5. Trace Data Flow

Phase 2: Pattern Analysis

1. Find Working Examples
2. Compare Against References
3. Identify Differences
4. Understand Dependencies

Phase 3: Hypothesis and Testing

1. Form Single Hypothesis
2. Test Minimally
3. Verify Before Continuing

Phase 4: Implementation

1. Create Failing Test Case
2. Implement Single Fix
3. Verify Fix
4. If 3+ Fixes Failed: Question Architecture

Red Flags - STOP and Follow Process

• "Quick fix for now, investigate later"
• "Just try changing X and see if it works"
• "I don't fully understand but this might work"
• Proposing solutions before tracing data flow

Quick Reference