Break the Loop - Deep Bug Analysis

When debug is complete, use this for deep analysis to break the "fix bug -> forget -> repeat" cycle.

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Analysis Framework

Analyze the bug you just fixed from these 5 dimensions:

1. Root Cause Category

Which category does this bug belong to?

Category	Characteristics	Example
A. Missing Spec	No documentation on how to do it	New feature without checklist
B. Cross-Layer Contract	Interface between layers unclear	API returns different format than expected
C. Change Propagation Failure	Changed one place, missed others	Changed function signature, missed call sites
D. Test Coverage Gap	Unit test passes, integration fails	Works alone, breaks when combined
E. Implicit Assumption	Code relies on undocumented assumption	Timestamp seconds vs milliseconds

2. Why Fixes Failed (if applicable)

If you tried multiple fixes before succeeding, analyze each failure:

• Surface Fix: Fixed symptom, not root cause
• Incomplete Scope: Found root cause, didn't cover all cases
• Tool Limitation: grep missed it, type check wasn't strict
• Mental Model: Kept looking in same layer, didn't think cross-layer

3. Prevention Mechanisms

What mechanisms would prevent this from happening again?

Type	Description	Example
Documentation	Write it down so people know	Update thinking guide
Architecture	Make the error impossible structurally	Type-safe wrappers
Compile-time	Strict type checking, no escape hatches	Signature change causes compile error
Runtime	Monitoring, alerts, scans	Detect orphan entities
Test Coverage	E2E tests, integration tests	Verify full flow
Code Review	Checklist, PR template	"Did you check X?"

4. Systematic Expansion

What broader problems does this bug reveal?