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 ashish7802/awesome-api-skills --skill vitestgit clone --depth 1 https://github.com/ashish7802/awesome-api-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/ashish7802/awesome-api-skills/vitest)<a href="https://agentmods.dev/skills/ashish7802/awesome-api-skills/vitest"><img src="https://agentmods.dev/badge/skills/ashish7802/awesome-api-skills/vitest/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/ashish7802/awesome-api-skills/vitest"><img src="https://agentmods.dev/badge/skills/ashish7802/awesome-api-skills/vitest.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00000 | $0.00651 |
| Opus 5 | $0.00000 | $0.00326 |
| Sonnet 5 | $0.00000 | $0.00130 |
| Haiku 4.5 | $0.00000 | $0.00065 |
Grade A, and why
vitest 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 5d 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 — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Vitest Skill
Next generation testing framework powered by Vite.
Ecosystem Graph Preview
graph LR
vitest["vitest"]:::core
classDef core fill:#f9f,stroke:#333,stroke-width:4px;
vitest -- "works well with" --> playwright
vitest -- "works well with" --> react
Recommended Next Skills
- playwright (Score: 0.85) Why: Direct relationship, Both are Testing, Shared ecosystem (javascript), Logical next step
- react (Score: 0.65) Why: Direct relationship, Shared ecosystem (javascript), Logical next step
- biome (Score: 0.4) Why: Both are Developer Tools, Shared ecosystem (javascript), Can deploy to any
Quick Start
Vitest is a blazing fast unit test framework powered by Vite. It is a drop-in replacement for Jest but significantly faster as it shares the same configuration and transformation pipeline as Vite.
npm install -D vitest
Production Patterns
Setup Files
Instead of importing beforeEach and describe manually in every test file, you can enable globals: true in your vitest.config.ts. Use a setupFiles array to mock global browser APIs (like fetch or localStorage) before any tests run.
Architecture & Scaling
Worker Threads
Vitest runs tests in isolated worker threads. This prevents global state mutations in one test from leaking and corrupting another test. This parallel execution is why Vitest is so fast.
Error Recovery
If tests randomly timeout in CI but pass locally, it is likely because your CI pipeline has significantly fewer CPU cores than your M-series MacBook. Use poolOptions: { threads: { maxThreads: 2 } } in CI to prevent thrashing.
Security Notes
Tests often require API keys. Never commit real API keys to .env.test. Always use msw (Mock Service Worker) to intercept network requests at the network level and return stubbed JSON responses, guaranteeing your test suite never hits real infrastructure.
What ships with it
2 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.
- 5d ago First seen · 67 lines · 0 tokens per session scan A ccd56ede55f6
vitest is a skill published in the GitHub repository ashish7802/awesome-api-skills (13 stars, last pushed 8d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 651 tokens. 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 2026-09-03.
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test-with-examples
For example-driven development: test cases as specifications, input/output pairs, documentation through examples.
verify-solution-properties
For solution checking: independent verification that result is correct, separate from how it was computed.
verify-with-inline-tests
For test co-location: tests in same file as code, run with main, tests as documentation and examples.
unit-test-generator
Convert changed behavior into focused unit and integration test cases.