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 pledgeandgrow/pledge-skills --skill jestgit clone --depth 1 https://github.com/pledgeandgrow/pledge-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/pledgeandgrow/pledge-skills/jest)<a href="https://agentmods.dev/skills/pledgeandgrow/pledge-skills/jest"><img src="https://agentmods.dev/badge/skills/pledgeandgrow/pledge-skills/jest/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/pledgeandgrow/pledge-skills/jest"><img src="https://agentmods.dev/badge/skills/pledgeandgrow/pledge-skills/jest.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 | $0.00032 | $0.01278 |
| Opus 5 | $0.00016 | $0.00639 |
| Sonnet 5 | $0.00006 | $0.00256 |
| Haiku 4.5 | $0.00003 | $0.00128 |
Grade A, and why
jest-docs 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 11d 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.get.mockResolvedValue({ data: { name: 'Bob' } }); How it starts
The opening of the file, as written. The whole thing — 127 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Jest Skill
Jest — A delightful JavaScript testing framework with a focus on simplicity. Version: Jest 30.x | Docs: jestjs.io
Quick Reference
| Topic | File | Sections |
|---|---|---|
| Getting Started & Core Concepts | getting-started.md |
Installation, first test, CLI usage, configuration (Babel, TypeScript, bundlers, ESLint), matchers, async testing, setup/teardown, mock functions |
| API Reference | api.md |
Globals (test, describe, before/after hooks, .each, .concurrent, .failing, .todo), expect matchers, jest object (mock modules, mock functions, fake timers, misc), mock function API, CLI options, configuration options |
| Guides & Advanced | guides.md |
Snapshot testing, timer mocks, manual mocks, ECMAScript modules, webpack integration, watch plugins, migration guide, testing frameworks (React/Vue/Angular/Express/Next.js), Puppeteer, MongoDB, DynamoDB, architecture |
Core Concepts
- Test Runner: Jest runs tests in parallel with isolated environments for speed and reliability
- Assertions: Use
expect()with matchers liketoBe(),toEqual(),toContain(),toThrow() - Mock Functions:
jest.fn()creates mock functions to test code links, capture calls, and configure return values - Mock Modules:
jest.mock()replaces module dependencies with mocks for isolated testing - Snapshot Testing: Captures serialized output and compares against a reference snapshot file
- Fake Timers:
jest.useFakeTimers()replaces native timer functions for controlled time advancement - Code Coverage: Built-in coverage reporting via
--coverageflag with Istanbul/V8 providers - Watch Mode:
--watchre-runs only tests related to changed files for fast development feedback - Configuration:
jest.config.js,package.json"jest" key, or CLI flags; supports projects, transforms, moduleNameMapper - Test Environment:
node(default) orjsdom(browser simulation) or custom environments - Parallel Execution: Worker threads/processes with
--maxWorkersfor optimized CI performance
What ships with it
3 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.
- 11d ago First seen · 127 lines · 32 tokens per session scan A 3533be15deae
jest-docs is a skill published in the GitHub repository pledgeandgrow/pledge-skills (10 stars, last pushed 1mo ago), licensed MIT. It adds 32 tokens to every session and 1,278 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 2026-08-31.
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