Coverage
Map routes, components, APIs, and critical flows against existing Playwright-style specs so you see what is untested before you ship.
Overview
coverage is an agent skill most often used in Ship (also Build frontend, Build backend) that maps your app surface to existing specs and lists coverage gaps in a matrix.
Install
npx skills add https://github.com/alirezarezvani/claude-skills --skill coverageWhat is this skill?
- Triggers on phrases like “test coverage”, “coverage gaps”, and “what needs testing”
- Step 1: Explore subagent catalogs routes, interactive components, API endpoints, and user flows
- Step 2: Scans *.spec.ts / *.spec.js for page.goto, locators, mocks, and per-area test counts
- Step 3: Emits a Coverage Matrix table with ✅ Covered, ⚠️ Partial, and ❌ Missing rows
- Framework-aware route discovery (Next.js app/, React Router, Vue Router, backend controllers)
- Three-step workflow: map application surface, map existing tests, generate coverage matrix
- Coverage matrix uses ✅ Covered, ⚠️ Partial, and ❌ Missing status labels
Adoption & trust: 1.6k installs on skills.sh; 17.5k GitHub stars; 3/3 security scanners passed (skills.sh audits).
What problem does it solve?
You have scattered end-to-end tests but no single view of which routes, APIs, and flows still have zero or weak coverage.
Who is it for?
Solo builders on Next.js, React Router, or Vue apps who use *.spec.ts tests and want an agent-generated gap report before QA.
Skip if: Teams that only want Istanbul line-coverage percentages without mapping user journeys, or codebases with no spec files to analyze.
When should I use this skill?
User says "test coverage", "what's not tested", "coverage gaps", "missing tests", "coverage report", or "what needs testing".
What do I get? / Deliverables
You get a prioritized coverage matrix showing missing and partial areas so you can add targeted spec files before release.
- Markdown coverage matrix by area, route, and test count
- List of missing and partial flows (auth, checkout, onboarding, etc.)
Recommended Skills
Journey fit
Spans multiple journey phases - primary shelf plus alternate fits below.
Coverage gap analysis is shelved under Ship testing because its payoff is knowing what will fail in QA or production, though you often run it while still building features. Testing subphase matches the skill’s explicit goal: compare application surface to *.spec tests and emit a coverage matrix with missing areas.
Where it fits
After adding three new settings pages, run coverage to see which lack any spec.ts coverage.
When API controllers grow, map which endpoints are never mocked or hit in tests.
Generate the coverage matrix as a launch gate alongside your manual QA checklist.
How it compares
A structural test-gap checker driven by Explore—not a CI coverage percentage reporter or a test generator by itself.
Common Questions / FAQ
Who is coverage for?
Indie developers and small teams with Playwright-style specs who need a fast inventory of untested pages, components, and APIs.
When should I use coverage?
During Ship testing before launch, during Build frontend when routes multiply, or after major backend API changes when mocks may be stale.
Is coverage safe to install?
It reads your repo and invokes an Explore subagent; review the Security Audits panel on this page and avoid pointing it at secrets in test fixtures.
SKILL.md
READMESKILL.md - Coverage
# Analyze Test Coverage Gaps Map all testable surfaces in the application and identify what's tested vs. what's missing. ## Steps ### 1. Map Application Surface Use the `Explore` subagent to catalog: **Routes/Pages:** - Scan route definitions (Next.js `app/`, React Router config, Vue Router, etc.) - List all user-facing pages with their paths **Components:** - Identify interactive components (forms, modals, dropdowns, tables) - Note components with complex state logic **API Endpoints:** - Scan API route files or backend controllers - List all endpoints with their methods **User Flows:** - Identify critical paths: auth, checkout, onboarding, core features - Map multi-step workflows ### 2. Map Existing Tests Scan all `*.spec.ts` / `*.spec.js` files: - Extract which pages/routes are covered (by `page.goto()` calls) - Extract which components are tested (by locator usage) - Extract which API endpoints are mocked or hit - Count tests per area ### 3. Generate Coverage Matrix ``` ## Coverage Matrix | Area | Route | Tests | Status | |---|---|---|---| | Auth | /login | 5 | ✅ Covered | | Auth | /register | 0 | ❌ Missing | | Auth | /forgot-password | 0 | ❌ Missing | | Dashboard | /dashboard | 3 | ⚠️ Partial (no error states) | | Settings | /settings | 0 | ❌ Missing | | Checkout | /checkout | 8 | ✅ Covered | ``` ### 4. Prioritize Gaps Rank uncovered areas by business impact: 1. **Critical** — auth, payment, core features → test first 2. **High** — user-facing CRUD, search, navigation 3. **Medium** — settings, preferences, edge cases 4. **Low** — static pages, about, terms ### 5. Suggest Test Plan For each gap, recommend: - Number of tests needed - Which template from `templates/` to use - Estimated effort (quick/medium/complex) ``` ## Recommended Test Plan ### Priority 1: Critical 1. /register (4 tests) — use auth/registration template — quick 2. /forgot-password (3 tests) — use auth/password-reset template — quick ### Priority 2: High 3. /settings (4 tests) — use settings/ templates — medium 4. Dashboard error states (2 tests) — use dashboard/data-loading template — quick ``` ### 6. Auto-Generate (Optional) Ask user: "Generate tests for the top N gaps? [Yes/No/Pick specific]" If yes, invoke `/pw:generate` for each gap with the recommended template. ## Output - Coverage matrix (table format) - Coverage percentage estimate - Prioritized gap list with effort estimates - Option to auto-generate missing tests