Test Coverage Analysis

Trigger

• Keywords: check coverage, test coverage, coverage analysis, coverage gaps, check-coverage

When NOT to Use

• Test sufficiency review via Codex (use /codex-test-review)
• Generating tests (use /codex-test-gen)
• Running tests (use /verify)

Parent Skill Reference

See @skills/test-review/SKILL.md for Codex-based test review workflow.

Agent Dispatch

Agent({
  description: "Assess three-layer test coverage and identify gaps",
  subagent_type: "coverage-analyst",
  prompt: `Assess Unit / Integration / E2E test coverage for the feature docs at: $ARGUMENTS
Follow the steps defined in this skill.`
})

Task

Step 1: Read Feature Documentation

Read specified feature docs. Extract:

• Feature name and objectives
• Involved Service / Provider / Entity
• Core flows and boundary conditions

Step 2: Identify Related Source Code

Search related source code based on feature documentation. Build source code inventory.

Step 3: Map Test Files

Check whether each source file has corresponding tests (unit, integration, e2e).

Step 4: Analyze Coverage Gaps

For each source file:

1. Read source: Identify public methods, important branches, error handling
2. Read tests: Identify covered cases
3. Compare gaps: missing methods, uncovered branches, untested error scenarios

Step 5: Classify and Recommend

Severity	Description
🔴 Critical	Core logic, data writes, amount calculations
🟠 Major	Important branches, error handling
🟡 Minor	Edge cases, utility functions
⚪ Nice-to-have	Logging, formatting

Output

# Test Coverage Analysis Report

## Feature Overview
- Feature name: <from documentation>
- Documentation path: $ARGUMENTS
- Related modules: <list>

## Current Coverage
| Module | Source Path | Test Path | Coverage Status |
|--------|------------|-----------|----------------|

## Coverage Gaps
### 🔴 Critical
### 🟠 Major
### 🟡 Minor

## Recommended New Tests
| Priority | Test Type | Test Case | Target File |
|----------|-----------|-----------|-------------|

## Coverage Summary
| Metric | Status |
|--------|--------|
| Feature coverage | X/Y (Z%) |
| Happy path | ✅/❌ |
| Error path | ✅/❌ |
| Edge cases | ✅/❌ |