Yosemite-Crew: Skill for Claude Code

.agents/skills/frontend-testing/SKILL.md

frontend-testing is a skill for Claude Code, Codex from YosemiteCrew/Yosemite-Crew. It costs 36 tokens per session (3,178 once invoked), scanned A, original, no licence file.

A guide to testing the frontend with Jest and React Testing Library, tools for checking JavaScript code and React user interfaces.

In plain words
What is it for?
Writing or fixing tests in apps/frontend, running targeted tests, checking coverage, and mocking Zustand state.
Why use it?
It provides the project’s testing rules and points out common problems that can make tests unreliable or incomplete.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing. Also seen: installed under .agents/ (shared by several agents).

This is YosemiteCrew/Yosemite-Crew's own configuration. It tells Claude Code and Codex how to work on Yosemite-Crew itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything Yosemite-Crew configures →

Reuse

Borrowing it

Nothing to install: this file belongs to YosemiteCrew/Yosemite-Crew. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/YosemiteCrew/Yosemite-Crew/main/.agents/skills/frontend-testing/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/YosemiteCrew/Yosemite-Crew

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for frontend-testing

README.md
[![agentmods](https://agentmods.dev/badge/skills/yosemitecrew/yosemite-crew/frontend-testing.svg)](https://agentmods.dev/skills/yosemitecrew/yosemite-crew/frontend-testing)
Your own site
<a href="https://agentmods.dev/skills/yosemitecrew/yosemite-crew/frontend-testing"><img src="https://agentmods.dev/badge/skills/yosemitecrew/yosemite-crew/frontend-testing.svg" alt="Measured on agentmods" height="20"></a>
Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,178 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium MCP Rug Pull · line 77
    npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.
    Fix: Pin the version: npx @scope/[email protected]
How audits are shown
Origin unknown 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 5.1 $0.00036 $0.03178
Opus 5 $0.00018 $0.01589
Sonnet 5 $0.00007 $0.00636
Haiku 4.5 $0.00004 $0.00318

Measured 8d ago against content hash 4f83096bcf77, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

frontend-testing 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 8d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

### `axios.isAxiosError` mock — use `jest.mock("axios", ...)` not `jest.spyOn`
.agents/skills/frontend-testing/SKILL.md · 329 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 8d ago First seen · 329 lines · 36 tokens per session scan A 4f83096bcf77

Subscribe to this mod's changes

frontend-testing is a skill published in the GitHub repository YosemiteCrew/Yosemite-Crew (2,020 stars, last pushed today), with no licence file. It adds 36 tokens to every session and 3,178 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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