addyosmani/agent-skills is a collection of reusable workflows, quality checks, commands, and other instructions that guide AI coding agents through software development. It is for developers who want agents to follow consistent engineering practices, and the catalogue entries are its packaged skills, commands, agents, plugins, instructions, and hooks.
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.
git clone --depth 1 https://github.com/addyosmani/agent-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/commands/addyosmani/agent-skills/test)<a href="https://agentmods.dev/commands/addyosmani/agent-skills/test"><img src="https://agentmods.dev/badge/commands/addyosmani/agent-skills/test/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/commands/addyosmani/agent-skills/test"><img src="https://agentmods.dev/badge/commands/addyosmani/agent-skills/test.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 | $0.00023 | $0.00152 |
| Opus 5.5 | $0.00009 | $0.00061 |
| Sonnet 5.5 | $0.00005 | $0.00030 |
| Haiku 4.5 | $0.00002 | $0.00015 |
Grade A, and why
test 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 1mo 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.
Copies of this mod
8 near-identical copies found in the catalogue:
What it actually says
Invoke the agent-skills:test-driven-development skill.
For new features:
- Write tests that describe the expected behavior (they should FAIL)
- Implement the code to make them pass
- Refactor while keeping tests green
For bug fixes (Prove-It pattern):
- Write a test that reproduces the bug (must FAIL)
- Confirm the test fails
- Implement the fix
- Confirm the test passes
- Run the full test suite for regressions
For browser-related issues, also invoke agent-skills:browser-testing-with-devtools to verify with Chrome DevTools MCP.
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.
- 1mo ago First seen · 20 lines · 23 tokens per session scan A 62f72b64cfac
test is a command published in the GitHub repository addyosmani/agent-skills (108,203 stars, last pushed 5d ago), licensed MIT. It adds 23 tokens to every session and 152 once invoked, about $0.0001 per session on Opus 5.5. 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.
Other commands, from other repositories
test
A test-driven development workflow, or TDD, where tests describing the expected behavior are written before the implementation. For bugs, it first adds a test that reproduces the failure.
test
Run TDD workflow — write failing tests, implement, verify. For bugs, use the Prove-It pattern.
build
A command for carrying out the next unfinished coding task from a plan, including writing tests, implementing the change, checking the project, and committing it. TDD, or test-driven development, means writing a failing test before the code that makes it pass.
constraints
A command for defining a project's quality standards through a short interview and a written CONSTRAINTS.md file. It records checks, thresholds, exceptions, and commands for enforcing them.
test
Run, author, or set up tests: run and repair, QA pass, TDD, Playwright E2E, coverage gates, or CI init.
tdd
Start test-driven development workflow for writing code.