Coverage Gaps Auditor (L3 Worker) Skill

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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.

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

Workflow

Parse context — extract fields, determine scan_path (domain-aware if specified) ELSE: scan_path = codebase_root domain_name = null
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)
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
Collect missing tests
- Tag each finding with domain: domain_name (if domain-aware)
Calculate score
Return JSON with domain metadata
- Include domain and scan_path fields (if domain-aware)

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

Return JSON to coordinator:

{
  "category": "Coverage Gaps",
  "score": 6,
  "total_issues": 10,
  "critical": 3,
  "high": 4,
  "medium": 2,
  "low": 1,
  "checks": [
    {"id": "line_coverage", "name": "Line Coverage", "status": "passed", "details": "85% coverage (threshold: 80%)"},
    {"id": "branch_coverage", "name": "Branch Coverage", "status": "warning", "details": "72% coverage (threshold: 75%)"},
    {"id": "function_coverage", "name": "Function Coverage", "status": "passed", "details": "90% coverage (threshold: 80%)"},
    {"id": "critical_gaps", "name": "Critical Gaps", "status": "failed", "details": "3 Money flows, 2 Security flows untested"}
  ],
  "domain": "orders",
  "scan_path": "src/orders",
  "findings": [
    {
      "severity": "CRITICAL",
      "location": "src/orders/services/order.ts:45",
      "issue": "Missing E2E test for applyDiscount() (Priority 25, Money flow)",
      "principle": "Coverage Gaps / Money Flow",
      "recommendation": "Add E2E test: applyDiscount() with edge cases (negative discount, max discount, currency rounding)",
      "effort": "M"
    },
    {
      "severity": "HIGH",
      "location": "src/orders/repositories/order.ts:78",
      "issue": "Missing Integration test for orderTransaction() rollback (Priority 18, Data Integrity)",
      "principle": "Coverage Gaps / Data Integrity",
      "recommendation": "Add Integration test verifying transaction rollback on failure",
      "effort": "M"
    }
  ]
}

Note: domain and scan_path fields included only when domain_mode="domain-aware".

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 (including domain_mode and 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
JSON returned to coordinator with domain metadata

Reference Files

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

Agent Skills: Coverage Gaps Auditor (L3 Worker)

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