wrdn-effect-vitest-tests

Testing rules for Effect-based TypeScript projects using Vitest, a JavaScript testing tool.

In plain words
What is it for?
Use it when lint reports direct Vitest imports or conditional expect calls, so tests can be rewritten with the project’s required helpers and clearer cases.
Why use it?
It prevents inconsistent test imports and assertions hidden inside conditional branches, which can make tests harder to check and maintain.

Skill for Claude CodeCodex

Install

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.

agentmods
npx agentmods add skills/usefulsoftwareco/executor/wrdn-effect-vitest-tests
Any agent
npx skills add UsefulSoftwareCo/executor --skill wrdn-effect-vitest-tests
Clone the repo
git clone --depth 1 https://github.com/UsefulSoftwareCo/executor

Made for: Claude Code, Codex.

Per session 29 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 200 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00029 $0.00200
Opus 5 $0.00015 $0.00100
Sonnet 5 $0.00006 $0.00040
Haiku 4.5 $0.00003 $0.00020

Measured 2d ago against content hash d3835d20da79, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

wrdn-effect-vitest-tests 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 2d 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

.agents/skills/wrdn-effect-vitest-tests/SKILL.md · 30 lines

What it actually says

Use @effect/vitest for tests in this repo.

Fix Shape

  • Import describe, it, expect, and helpers from @effect/vitest.
  • Import utility helpers from @effect/vitest/utils when needed.
  • Do not import from raw vitest except in config or tooling files.
  • Do not put expect(...) behind if, ternary, logical, or switch branches.
  • Split conditional behavior into separate tests, or assert the branch condition and expected value explicitly.

Bad

if (result.ok) {
  expect(result.value).toBe("x");
}

Good

expect(result).toEqual({ ok: true, value: "x" });
Changes

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.

  1. 2d ago First seen · 30 lines · 29 tokens per session scan A d3835d20da79

Subscribe to this mod's changes

wrdn-effect-vitest-tests is a skill published in the GitHub repository UsefulSoftwareCo/executor (3,494 stars, last pushed today), licensed MIT. It adds 29 tokens to every session and 200 once invoked, about $0.0001 per session on Opus 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 2026-08-30.

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