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E2E Critical Coverage Auditor (L3 Worker)

Specialized worker auditing E2E test coverage for critical paths (risk-based).

Purpose & Scope

• Worker in ln-630 coordinator pipeline
• Audit E2E Critical Coverage (Category 2: High Priority)
• Validate E2E coverage for critical paths (Money/Security/Data Priority ≥20)
• Validate E2E coverage for core user journeys (Priority 15-19)
• Identify wasteful E2E tests (Usefulness Score <15)
• Calculate compliance score (X/10)

Inputs (from Coordinator)

MANDATORY READ: Load shared/references/audit_worker_core_contract.md.

Receives contextStore with: tech_stack, testFilesMetadata, codebase_root, output_dir.

Workflow

MANDATORY READ: Load shared/references/two_layer_detection.md for detection methodology.

1. Parse Context: Extract tech stack, critical paths, user journeys, test file list, output_dir from contextStore
2. Identify Critical Paths (Layer 1): Scan codebase for critical paths (Money, Security, Data) 2b) Context Analysis (Layer 2 — MANDATORY): For each candidate critical path, ask:
   • Is this a helper function called from an already-E2E-tested path? → downgrade to MEDIUM
   • Is this already covered by integration test with real assertions? → downgrade to LOW
   • Is keyword match a false positive (e.g., calculateDiscount() is pure math, already unit-tested)? → skip
3. Identify Core Journeys: Identify core user journeys (multi-step flows)
4. Check Critical Path Coverage: Check E2E coverage for critical paths (Priority >=20)
5. Check Journey Coverage: Check E2E coverage for user journeys (Priority 15-19)
6. Validate E2E Tests: Validate existing E2E tests (Usefulness Score >=15)
7. Collect Findings: Record each violation with severity, location (file:line), effort estimate (S/M/L), recommendation
8. Calculate Score: Count violations by severity, calculate compliance score (X/10)
9. Write Report: Build full markdown report in memory per shared/templates/audit_worker_report_template.md, write to {output_dir}/632-e2e-priority.md in single Write call
10. Return Summary: Return minimal summary to coordinator (see Output Format)

Audit Rules

1. Critical Path E2E Coverage

Rule: Every critical path MUST have E2E test

Critical Paths (Priority ≥20):

• Money (Priority 25): Payment processing, refunds, discounts, tax calculation
• Security (Priority 25): Login, auth, password reset, token refresh, permissions
• Data Export (Priority 20): Reports, CSV generation, data migration

Detection:

1. Scan codebase for critical keywords: payment, refund, login, auth, export
2. Extract critical functions/endpoints
3. Check if E2E test exists for each critical path
4. Missing E2E for Priority ≥20 → CRITICAL severity

Severity:

• CRITICAL: No E2E for Priority 25 (Money, Security)
• HIGH: No E2E for Priority 20 (Data Export)
• Downgrade when: Function is helper called from already-E2E-tested path → MEDIUM. Already covered by integration test → LOW

Recommendation: Add E2E tests for critical paths immediately

Effort: M

2. Core User Journey E2E Coverage

Rule: Multi-step critical flows MUST have E2E test

Core Journeys (Priority 15-19):

• Registration → Email verification → First login (Priority 16)
• Product search → Add to cart → Checkout (Priority 18)
• File upload → Processing → Download result (Priority 15)

Detection:

1. Identify multi-step flows in routes/controllers
2. Check if end-to-end journey test exists
3. Missing E2E for Priority ≥15 → HIGH severity

Severity:

• HIGH: Missing E2E for core user journey (Priority ≥15)
• MEDIUM: Incomplete journey coverage (only partial steps tested)

Recommendation: Add end-to-end journey tests

Effort: M-L

3. E2E Test Usefulness Validation

Rule: Every E2E test MUST justify Priority ≥15

Check: For each E2E test, calculate Usefulness Score = Impact × Probability

• If Score <15 → Flag as "Potentially wasteful E2E"
• Recommendation: Convert to Integration or Unit test (cheaper)

Example:

• E2E test for "API returns 200 OK" → Impact 2, Probability 1 → Score 2 → WASTEFUL
• E2E test for "Payment with discount calculates correctly" → Impact 5, Probability 5 → Score 25 → VALUABLE

Severity:

• MEDIUM: E2E test with Usefulness Score <15
• LOW: E2E test with Score 10-14 (review needed)

Recommendation: Convert low-value E2E to Integration/Unit or remove

Effort: S

Scoring Algorithm

MANDATORY READ: Load shared/references/audit_worker_core_contract.md and shared/references/audit_scoring.md.

Severity mapping:

• Missing E2E for Priority 25 (Money, Security) → CRITICAL
• Missing E2E for Priority 20 (Data Export) → HIGH
• Missing E2E for Priority 15-19 (Core Journeys) → HIGH
• Wasteful E2E (Score <15) → MEDIUM
• Incomplete journey coverage → LOW

Output Format

MANDATORY READ: Load shared/references/audit_worker_core_contract.md and shared/templates/audit_worker_report_template.md.

Write report to {output_dir}/632-e2e-priority.md with category: "E2E Critical Coverage" and checks: critical_path_coverage, user_journey_coverage, e2e_usefulness_validation.

Return summary to coordinator:

Report written: docs/project/.audit/ln-630/{YYYY-MM-DD}/632-e2e-priority.md
Score: X.X/10 | Issues: N (C:N H:N M:N L:N)

Critical Rules

MANDATORY READ: Load shared/references/audit_worker_core_contract.md.

• Do not auto-fix: Report only
• Risk-based only: Prioritize by business impact (Money > Security > Data), not by code coverage percentage
• Effort realism: S = <1h, M = 1-4h, L = >4h
• Usefulness Score threshold: Only flag E2E tests with Score <15 as wasteful
• No pyramid enforcement: Do not recommend E2E/Integration/Unit ratios — focus on critical path coverage

Definition of Done

MANDATORY READ: Load shared/references/audit_worker_core_contract.md.

• contextStore parsed successfully (including output_dir)
• Critical paths identified (Money, Security, Data) with Priority scores
• All 3 checks completed (critical path coverage, user journey coverage, E2E usefulness validation)
• Findings collected with severity, location, effort, recommendation
• Score calculated using penalty algorithm
• Report written to {output_dir}/632-e2e-priority.md (atomic single Write call)
• Summary returned to coordinator

Reference Files

• Audit output schema: shared/references/audit_output_schema.md

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Version: 3.0.0 Last Updated: 2025-12-23