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name: rca-verification description: Methods for validating root cause analyses. Provides checklists for 5 Whys depth, execution path accuracy, and fix strategy soundness. Use when reviewing RCA reports.

RCA Verification Skill

This skill provides verification patterns for validating root cause analyses.

When to Use

• After RCA Analyst produces rca-report.md
• When validating 5 Whys methodology application
• When assessing fix strategy soundness
• Before proceeding to implementation planning

Verification Categories

1. 5 Whys Depth Validation

The 5 Whys should reach a fundamental cause, not just a symptom.

Quality Checklist:

Red Flags (Shallow Root Causes):

These are symptoms, not root causes:

Good Root Causes (Fundamental):

These cannot be explained by more "Why" questions:

• ✅ "The function was designed for authenticated contexts but reused for public endpoints without null checks"
• ✅ "The timeout was hardcoded based on average response time, not accounting for load spikes"
• ✅ "The cache invalidation logic doesn't cover the mutation path added in PR #123"
• ✅ "No documentation governance process exists to ensure template completeness"
• ✅ "The error handling strategy assumes all failures are transient, but this failure is permanent"

2. Execution Path Verification

All file:line references must be verified against the actual codebase.

For each reference:

1. File Exists: Use #tool:search/fileSearch to confirm file path
2. Line Accurate: Use #tool:read/readFile to verify content at line
3. Content Matches: Compare description to actual code
4. Call Chain Valid: Use #tool:search/usages to verify connections

Verification Table Template:

Copy| Step | File:Line | Exists | Content Matches | Verdict |
|------|-----------|--------|-----------------|---------|
| Entry | `src/file.ts:45` | ✅ | ✅ | ✅ PASS |
| Step 2 | `src/other.ts:120` | ✅ | ⚠️ Line off by 3 | ⚠️ MINOR |
| Fault | `src/bug.ts:78` | ❌ | N/A | ❌ FAIL |

Correction Format:

Copy| Original | Actual | Impact |
|----------|--------|--------|
| `file.ts:45` | `file.ts:48` (line shifted) | Low |
| `missing.ts:10` | File not found | 🔴 Critical |

3. Fix Strategy Assessment

The fix must address the root cause, not just mask the symptom.

Checklist:

Common Issues:

1. Symptom Masking: Fix adds null check instead of fixing why null occurs
2. Risk Underestimation: Claims "Low risk" for change affecting many files
3. Trivial Alternatives: "Alternative" is just minor variation of primary
4. Missing Side Effects: Doesn't consider impact on callers

4. Side Effect Analysis

Check what else might be affected by the proposed fix.

For each modified component:

1. Find all usages with #tool:search/usages
2. Assess impact on each caller
3. Flag breaking changes
4. Note edge cases

Risk Categories:

Output Templates

verified-rca.md Structure

Copy# Verified RCA: {TICKET-ID}

**Date**: {YYYY-MM-DD}
**Verifier**: AI Agent (RCA Verifier)
**Original RCA**: `rca-report.md`
**Status**: [VERIFIED / VERIFIED WITH NOTES / NEEDS REVISION]

---

## Verification Summary

| Category | Status | Issues | Confidence |
|----------|--------|--------|------------|
| 5 Whys Depth | ✅/⚠️/❌ | [count] | High/Medium/Low |
| Execution Path | ✅/⚠️/❌ | [count] | High/Medium/Low |
| Fix Strategy | ✅/⚠️/❌ | [count] | High/Medium/Low |
| Side Effects | ✅/⚠️/❌ | [count] | High/Medium/Low |

**Overall Confidence**: [HIGH / MEDIUM / LOW]

---

[Detailed sections for each category...]

---

## Recommendation

**Status**: [VERIFIED / VERIFIED WITH NOTES / NEEDS REVISION]

[Explanation and next steps...]

Status Definitions

Edge Cases

Simple Bugs (2-3 Whys)

Not all bugs need 5 Whys. Simple bugs may reach fundamental cause faster:

• Typo: 2 Whys may suffice if clearly a one-off mistake
• Simple Logic Error: 3 Whys may reach design decision
• Configuration Issue: 2-3 Whys may reach process gap

Verify: Even short chains must reach fundamental cause.

Complex Bugs (5+ Whys)

Deep analysis appropriate for:

• Architectural Issues: May need 5+ to reach design decisions
• Multi-Component Bugs: Need to trace across boundaries
• Recurring Issues: Must find why previous fixes didn't work

Watch for: Circular reasoning after 7+ Whys.

Process/Governance Root Causes

When root cause is absence of process:

• Valid: "No code review process caught this anti-pattern"
• Valid: "No documentation governance ensures completeness"
• Invalid: "Someone made a mistake" (too vague)

Verify: Process gap is specific and actionable.

Revision Loop Prevention

To prevent endless cycles between Verifier and Analyst:

1. Maximum 2 revision attempts before human escalation
2. Track recurring issues in verified-rca.md
3. Escalate if same issues persist

Escalation message:

Copy⚠️ REVISION LOOP DETECTED

This RCA has been revised [X] times with recurring issues.
Manual review required.

References

• RCA Analyst Agent: .github/agents/rca-analyst.agent.md
• RCA Verifier Agent: .github/agents/rca-verifier.agent.md
• Research Verifier Pattern: .github/agents/research-verifier.agent.md
• Bug Fixing Workflow: context/bug-fixing-workflow-design-plan.md