addyosmani/agent-skills
agent-skills
Production-grade engineering skills for AI coding agents.
GitHub metrics
- Stars
- 106K
- +5K this week
- Forks
- 11K
- 30-day growth
- —
- Open issues
- 59
| Day | GitHub stars |
|---|---|
| 2026-10-04 | 100835 |
| 2026-10-10 | 104287 |
| 2026-10-13 | 105822 |
What it does
Agent Skills is a repository of 25 Markdown workflows for AI coding agents, covering software work from specification and planning through testing, review, performance, security, deployment and documentation. Each skill is a SKILL.md process with triggers, steps, red flags, verification criteria and common rationalizations to counter.
The pack can be installed with the skills CLI or integrated with tools including Claude Code, Cursor, Gemini CLI, OpenCode, GitHub Copilot and Codex. Nine slash commands map development tasks to skills. /build auto can generate a plan and implement its tasks after one approval, while stopping on failures or risky steps.
This suits teams that want an agent to follow a defined engineering process instead of relying on isolated prompts. The repository also contains four review personas, shared checklists, evaluation cases and host-specific adapters. One installation limitation matters: installing a single skill through npx does not copy the repository-level references/ directory, so links to shared checklists are unavailable unless those files are supplied another way.
Why it matters
Coding agents can take shortcuts around specifications, tests and reviews. Agent Skills turns those stages into reusable workflows with verification gates, routing commands and specialist review personas. The project's comparison documentation distinguishes it by organizing work across the full development lifecycle, from defining a change through shipping it, rather than concentrating mainly on the inner coding loop.
Main features
- Includes 25 skills organized across the software development lifecycle.
- Provides nine slash commands for common development stages.
- Each skill includes verification criteria, red flags and step-by-step processes.
- Includes four specialist review personas.
- Provides shared checklists for testing, security, performance, accessibility and observability.
- Supports automatic skill activation in integrations that provide routing.
- Includes evaluation cases and CI tooling for skill behavior and routing.
Who it's for
- Developers using AI coding agents that accept Markdown instructions.
- Teams that want repeatable specification, testing, review and shipping workflows.
- Users of Claude Code, Cursor, Gemini CLI, OpenCode, Copilot or Codex.
- Maintainers who want security, performance and code-quality review workflows.
Strengths
- Covers work from requirements and planning through review and deployment.
- Uses explicit verification steps and exit criteria inside each skill.
- Has setup guidance for several coding-agent hosts.
- Includes specialist personas and reusable engineering checklists.
Limitations
- Single-skill `npx` installs omit the repository-level `references/` directory.
- Host integrations differ in how skills and commands are installed or discovered.
- Antigravity documentation notes wrapper-command discovery problems in affected releases.
Getting started
Install the whole pack, inspect the available skills first, or install one named skill.
npx skills add addyosmani/agent-skills
npx skills add addyosmani/agent-skills --list
npx skills add addyosmani/agent-skills --skill code-review-and-quality
npx skills add addyosmani/agent-skills --skill interview-me
npx skills add addyosmani/agent-skills --skill test-driven-development
Requirements: An AI coding agent that accepts Markdown instructions.
Always follow the official instructions in the README on GitHub. This overview is our summary, not a copy.
Sources
- addyosmani/agent-skillsRepositoryPrimarygithub.com
- agent-skills - production-grade engineering skills for AI coding agentsOfficial sitePrimaryskills.addy.ie
- github.com/addyosmani/agent-skills/blob/main/docs/getting-started.mdRepositoryPrimary
- github.com/addyosmani/agent-skills/issues/361RepositoryPrimary
- github.com/addyosmani/agent-skills/blob/main/docs/comparison.mdRepositoryPrimary
- github.com/addyosmani/agent-skills/blob/main/LICENSERepositoryPrimary
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