Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add bestdeejay-design/agent-skills --skill frontend-testinggit clone --depth 1 https://github.com/bestdeejay-design/agent-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/bestdeejay-design/agent-skills/frontend-testing)<a href="https://agentmods.dev/skills/bestdeejay-design/agent-skills/frontend-testing"><img src="https://agentmods.dev/badge/skills/bestdeejay-design/agent-skills/frontend-testing/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/bestdeejay-design/agent-skills/frontend-testing"><img src="https://agentmods.dev/badge/skills/bestdeejay-design/agent-skills/frontend-testing.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00243 | $0.03073 |
| Opus 5.5 | $0.00097 | $0.01229 |
| Sonnet 5.5 | $0.00049 | $0.00615 |
| Haiku 4.5 | $0.00024 | $0.00307 |
Grade A, and why
frontend-testing scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 208 lines — stays where its author put it; the contents beside it link to each section on GitHub.
frontend-testing
Define and scaffold frontend testing for production readiness. Our other
frontend skills (frontend-perfection, frontend-a11y, frontend-performance)
audit a built site; they run ZERO tests. This skill closes that gap: it tells
you what to test, which layer owns each concern, and hands you the config
to wire into CI. It is a process/knowledge + scaffolding skill, not a runtime
audit.
The 13 Testing rules → pyramid layer
Mapped 1:1 from the Front-End-Checklist "Testing" category. Each rule names the layer it belongs to and the reference file that scaffolds it.
| # | Rule (verbatim priority) | Layer | Scaffold |
|---|---|---|---|
| 1 | Write unit tests [High] | Unit | your unit runner (Vitest/Jest) |
| 2 | Write integration tests for key workflows [High] | Integration | your runner + MSW |
| 3 | Implement end-to-end testing [High] | E2E | references/playwright.config.ts, references/e2e-smoke.spec.ts |
| 4 | Use visual regression testing [Medium] | Visual | references/visual-regression.md |
| 5 | Include accessibility testing [High] | A11y | references/a11y-test.md |
| 6 | Test across all major browsers [High] | Cross-browser | references/playwright.config.ts (projects) |
| 7 | Test on real mobile devices and viewports [High] | Real-device | references/playwright.config.ts (Mobile projects) |
| 8 | Enforce performance budgets in CI [Medium] | Perf-budget | references/ci-perf-budget.yml |
| 9 | Use mutation testing to measure how well tests detect bugs [Medium] | Mutation | Stryker config note |
| 10 | Integrate real-time error monitoring in production [High] | Error-monitoring | Sentry note |
| 11 | Maintain test coverage thresholds [Medium] | Coverage | references/ci-perf-budget.yml (coverage gate) |
| 12 | Follow mocking best practices [Medium] | Mocking | mocking note |
| 13 | Implement consumer-driven contract testing for API boundaries [Medium] | Contract | references/contract-test.md |
Testing pyramid (shape, not just a list)
What ships with it
8 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago Changed · +5 lines 3c6e89e6214d
- 1mo ago First seen · 203 lines · 243 tokens per session scan A 10fd0904261e
frontend-testing is a skill published in the GitHub repository bestdeejay-design/agent-skills (5 stars, last pushed 1mo ago), licensed MIT. It adds 243 tokens to every session and 3,073 once invoked, about $0.0010 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
test-commander
Generate unit, integration, E2E, and visual regression tests following the Testing Trophy methodology (80% integration). Covers Vitest/Jest, Testing Library, Playwright, MSW for API mocking, snapshot strategy, visual regression (Chromatic/Percy/Playwright), test factories with Faker, and CI sharding. Use when user…
test-sweep
Run all test suites (unit, integration, API, E2E) and aggregate results into a summary report. Use after completing execution slices or before the Review Gate.
python-patterns
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javascript-testing-patterns
Implement comprehensive testing strategies using Jest, Vitest, and Testing Library for unit tests, integration tests, and end-to-end testing with mocking, fixtures, and test-driven development. Use when writing JavaScript/TypeScript tests, setting up test infrastructure, or implementing TDD/BDD workflows.
axiom-testing
Use when writing ANY test, debugging flaky tests, making tests faster, or choosing Swift Testing vs XCTest. Covers unit tests, UI tests, async testing, test architecture.
adk-setup
Sets up a local ADK Python development environment in a git clone of the open-source adk-python repository: a uv virtual environment, all dependency extras, pre-commit hooks, and a first unit-test run. Runs only when explicitly requested, never on its own. Use when asked to set up, bootstrap, or repair a development…