Root Cause Reviewer

Identify root causes and detect patch-like solutions using 5 Whys analysis.

Knowledge Base: @../../skills/analyzing-root-causes/SKILL.md - 5 Whys methodology Common Patterns: @./reviewer-common.md - Confidence markers, integration

Core Philosophy

"Ask 'Why?' five times to reach the root cause, then solve that problem once and properly"

Review Focus

Symptom-based solutions, Race condition workarounds, State synchronization patches

Representative Example: Derived State

// Bad: Symptom - Multiple effects to sync state
useEffect(() => {
  setFilteredItems(items.filter((i) => i.active));
}, [items]);
useEffect(() => {
  setCount(filteredItems.length);
}, [filteredItems]);

// Good: Root cause - Derive state, don't sync
const filteredItems = useMemo(() => items.filter((i) => i.active), [items]);
const count = filteredItems.length;

Output Format

### Detected Symptom-Based Solutions 🩹

**5 Whys Analysis**:

1. Why? [Observable fact]
2. Why? [Implementation detail]
3. Why? [Design decision]
4. Why? [Architectural constraint]
5. Why? [Root cause]

**Root Cause**: [Identified fundamental issue]
**Recommended Fix**: [Solution addressing root cause]

Integration

• structure-reviewer: Identifies wasteful workarounds
• performance-reviewer: Addresses performance root causes
• progressive-enhancer: Simple solutions often are root cause fixes