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 BjornMelin/dev-skills --skill vitest-devgit clone --depth 1 https://github.com/BjornMelin/dev-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/bjornmelin/dev-skills/vitest-dev)<a href="https://agentmods.dev/skills/bjornmelin/dev-skills/vitest-dev"><img src="https://agentmods.dev/badge/skills/bjornmelin/dev-skills/vitest-dev/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/bjornmelin/dev-skills/vitest-dev"><img src="https://agentmods.dev/badge/skills/bjornmelin/dev-skills/vitest-dev.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 | $0.00035 | $0.02254 |
| Opus 5 | $0.00017 | $0.01127 |
| Sonnet 5 | $0.00007 | $0.00451 |
| Haiku 4.5 | $0.00003 | $0.00225 |
Grade A, and why
vitest-dev scanned grade A with 1 finding 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 9d 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.
Runs shell commandslowCapability
Expected in a hook, worth knowing in a rule or an instructions file.
Vitest runs test files using a **pool** (`forks`, `threads`, `vmThreads`, `vmForks`). By default (Vitest v4 docs) it uses **`forks`**. `threads` can be faster but may break libraries that use native bindings; `forks` use The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
What ships with it
35 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.
- agents/openai.yaml 253 B
- checklists/ci-optimization.md 838 B
- checklists/pr-review.md 930 B
- checklists/test-plan.md 1.1 KB
- examples/next/__tests__/client-nav-button.test.tsx 672 B
- examples/next/__tests__/page.test.tsx 293 B
- examples/next/app/client-nav-button.tsx 272 B
- examples/next/app/page.tsx 160 B
- examples/react/Counter.test.tsx 590 B
- examples/react/Counter.tsx 288 B
- examples/unit/add.test.ts 348 B runs code
- examples/unit/add.ts 61 B runs code
- LICENSE 1.0 KB
- README.md 882 B
- references/00-official-docs-index.md 1.5 KB
- references/01-performance-playbook.md 4.5 KB
- references/02-anti-patterns.md 2.3 KB
- references/03-nextjs-16-setup.md 1.6 KB
- references/04-mocking-cheatsheet.md 1.2 KB
- references/05-cli-cheatsheet.md 785 B
- references/06-coverage-and-typecheck.md 1.1 KB
- scripts/vitest-ci.sh 382 B runs code
- scripts/vitest-flake-check.mjs 920 B runs code
- scripts/vitest-local.sh 223 B runs code
- scripts/vitest-merge-reports.mjs 562 B runs code
- scripts/vitest-shard.mjs 1.1 KB runs code
- SKILL.json 340 B
- templates/setup-node.ts 141 B runs code
- templates/setup-tests.ts 222 B runs code
- templates/test-utils/msw.ts 331 B runs code
- templates/test-utils/next.tsx 796 B
- templates/test-utils/react.tsx 464 B
- templates/vitest.config.base.ts 1.1 KB runs code
- templates/vitest.config.next.mts 630 B
- templates/vitest.config.projects.ts 867 B runs code
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.
- 9d ago First seen · 197 lines · 35 tokens per session scan A f917d64950b5
vitest-dev is a skill published in the GitHub repository BjornMelin/dev-skills (7 stars, last pushed 4d ago), with no licence file. It adds 35 tokens to every session and 2,254 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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