Paths: File paths (shared/, references/, ../ln-*) are relative to skills repo root. If not found at CWD, locate this SKILL.md directory and go up one level for repo root.

Coverage Gaps Auditor (L3 Worker)

Specialized worker identifying missing tests for critical business logic.

Purpose & Scope

• Worker in ln-630 coordinator pipeline
• Audit Coverage Gaps (Category 4: High Priority)
• Identify untested critical paths
• Classify by category (Money, Security, Data, Core Flows)
• Calculate compliance score (X/10)

Inputs (from Coordinator)

MANDATORY READ: Load shared/references/task_delegation_pattern.md#audit-coordinator--worker-contract for contextStore structure.

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

Domain-aware: Supports domain_mode + current_domain (see audit_output_schema.md#domain-aware-worker-output).

Workflow

1. Parse context — extract fields, determine scan_path (domain-aware if specified) ELSE: scan_path = codebase_root domain_name = null

2. Identify critical paths in scan_path (not entire codebase)

   • Scan production code in scan_path for money/security/data keywords
   • All Grep/Glob patterns use scan_path (not codebase_root)
   • Example: Grep(pattern="payment|refund|discount", path=scan_path)

3. Check test coverage for each critical path

   • Search ALL test files for coverage (tests may be in different location than production code)
   • Match by function name, module name, or test description

4. Collect missing tests

   • Tag each finding with domain: domain_name (if domain-aware)

5. Calculate Score: Count violations by severity, calculate compliance score (X/10)

6. Write Report: Build full markdown report in memory per shared/templates/audit_worker_report_template.md, write to {output_dir}/634-coverage-gaps.md (or {output_dir}/634-coverage-gaps-{domain}.md if domain-aware) in single Write call

7. Return Summary: Return minimal summary to coordinator (see Output Format)

Critical Paths Classification

1. Money Flows (Priority 20+)

What: Any code handling financial transactions

Examples:

• Payment processing (/payment, processPayment())
• Discounts/promotions (calculateDiscount(), applyPromoCode())
• Tax calculations (calculateTax(), getTaxRate())
• Refunds (processRefund(), /refund)
• Invoices/billing (generateInvoice(), createBill())
• Currency conversion (convertCurrency())

Min Priority: 20

Why Critical: Money loss, fraud, legal compliance

2. Security Flows (Priority 20+)

What: Authentication, authorization, encryption

Examples:

• Login/logout (/login, authenticate())
• Token refresh (/refresh-token, refreshAccessToken())
• Password reset (/forgot-password, resetPassword())
• Permissions/RBAC (checkPermission(), hasRole())
• Encryption/hashing (custom crypto logic, NOT bcrypt/argon2)
• API key validation (validateApiKey())

Min Priority: 20

Why Critical: Security breach, data leak, unauthorized access

3. Data Integrity (Priority 15+)

What: CRUD operations, transactions, validation

Examples:

• Critical CRUD (createUser(), deleteOrder(), updateProduct())
• Database transactions (withTransaction())
• Data validation (custom validators, NOT framework defaults)
• Data migrations (runMigration())
• Unique constraints (checkDuplicateEmail())

Min Priority: 15

Why Critical: Data corruption, lost data, inconsistent state

4. Core User Journeys (Priority 15+)

What: Multi-step flows critical to business

Examples:

• Registration → Email verification → Onboarding
• Search → Product details → Add to cart → Checkout
• Upload file → Process → Download result
• Submit form → Approval workflow → Notification

Min Priority: 15

Why Critical: Broken user flow = lost customers

Audit Rules

1. Identify Critical Paths

Process:

• Scan codebase for money-related keywords: payment, refund, discount, tax, price, currency
• Scan for security keywords: auth, login, password, token, permission, encrypt
• Scan for data keywords: transaction, validation, migration, constraint
• Scan for user journeys: multi-step flows in routes/controllers

2. Check Test Coverage

For each critical path:

• Search test files for matching test name/description
• If NO test found → add to missing tests list
• If test found but inadequate (only positive, no edge cases) → add to gaps list

3. Categorize Gaps

Severity by Priority:

• CRITICAL: Priority 20+ (Money, Security)
• HIGH: Priority 15-19 (Data, Core Flows)
• MEDIUM: Priority 10-14 (Important but not critical)

4. Provide Justification

For each missing test:

• Explain WHY it's critical (money loss, security breach, etc.)
• Suggest test type (E2E, Integration, Unit)
• Estimate effort (S/M/L)

Scoring Algorithm

MANDATORY READ: Load shared/references/audit_scoring.md for unified scoring formula.

Severity mapping by Priority:

• Priority 20+ (Money, Security) missing test → CRITICAL
• Priority 15-19 (Data Integrity, Core Flows) missing test → HIGH
• Priority 10-14 (Important) missing test → MEDIUM
• Priority <10 (Nice-to-have) → LOW

Output Format

MANDATORY READ: Load shared/templates/audit_worker_report_template.md for file format.

Write report to {output_dir}/634-coverage-gaps.md (global) or {output_dir}/634-coverage-gaps-{domain}.md (domain-aware) with category: "Coverage Gaps" and checks: money_flow_coverage, security_flow_coverage, data_integrity_coverage, core_journey_coverage.

Return summary to coordinator:

Report written: docs/project/.audit/ln-630/{YYYY-MM-DD}/634-coverage-gaps.md
Score: X.X/10 | Issues: N (C:N H:N M:N L:N)

Critical Rules

• Domain-aware scanning: If domain_mode="domain-aware", scan ONLY scan_path production code (not entire codebase)
• Tag findings: Include domain field in each finding when domain-aware
• Test search scope: Search ALL test files for coverage (tests may be in different location than production code)
• Match by name: Use function name, module name, or test description to match tests to production code

Definition of Done

• contextStore parsed successfully (including output_dir, domain_mode, current_domain)
• scan_path determined (domain path or codebase root)
• Critical paths identified in scan_path (Money, Security, Data, Core Flows)
• Test coverage checked for each critical path
• Missing tests collected with severity, priority, justification, domain
• Score calculated using penalty algorithm
• Report written to {output_dir}/634-coverage-gaps.md or 634-coverage-gaps-{domain}.md (atomic single Write call)
• Summary returned to coordinator

Reference Files

• Worker report template: shared/templates/audit_worker_report_template.md
• Audit scoring formula: shared/references/audit_scoring.md
• Audit output schema: shared/references/audit_output_schema.md

---

Version: 3.0.0 Last Updated: 2025-12-23