Addy Osmani Agent Skills
Production-grade engineering skills for AI coding agents that encode workflows, quality gates, and best practices senior engineers use when building software.
At a Glance
About Addy Osmani Agent Skills
Agent Skills by Addy Osmani is an open-source collection of 20 production-grade engineering skills designed to guide AI coding agents through every phase of software development. Skills encode the workflows, quality gates, and best practices that senior engineers apply — from idea refinement and spec writing through to shipping and monitoring. Rather than generic prompts, each skill is a structured, step-by-step workflow with verification gates and anti-rationalization tables that prevent agents from skipping critical steps.
- 20 Core Skills covering the full development lifecycle: Define, Plan, Build, Verify, Review, and Ship phases — each packaged as a
SKILL.mdwith steps, checkpoints, and exit criteria. - 7 Slash Commands (
/spec,/plan,/build,/test,/review,/code-simplify,/ship) that map directly to the development lifecycle and activate the right skills automatically. - Multi-agent support — works with Claude Code (via marketplace install), Cursor, Gemini CLI, Windsurf, OpenCode, GitHub Copilot, Kiro IDE, and any agent that accepts Markdown system prompts.
- Agent Personas — three pre-configured specialist personas (code-reviewer, test-engineer, security-auditor) for targeted, role-specific reviews.
- Reference Checklists for testing patterns, security (OWASP Top 10), performance (Core Web Vitals), and accessibility (WCAG 2.1 AA).
- Anti-rationalization tables in every skill document common excuses agents use to skip steps (e.g., "I'll add tests later") with documented counter-arguments.
- Verification-first design — every skill ends with evidence requirements (tests passing, build output, runtime data) so "seems right" is never sufficient.
- Google engineering practices baked in — Hyrum's Law, Beyonce Rule, test pyramid, trunk-based development, Shift Left, Chesterton's Fence, and more are embedded directly into workflows.
- Progressive disclosure —
SKILL.mdis the entry point; supporting references load only when needed to keep token usage minimal. - MIT License — free to use, modify, and distribute in personal projects, teams, and commercial tools.
Community Discussions
Be the first to start a conversation about Addy Osmani Agent Skills
Share your experience with Addy Osmani Agent Skills, ask questions, or help others learn from your insights.
Pricing
Open Source (MIT)
Fully free and open-source under the MIT License. Use, modify, and distribute freely.
- 20 core engineering skills
- 7 slash commands
- 3 agent personas
- 4 reference checklists
- Session lifecycle hooks
Capabilities
Key Features
- 20 production-grade engineering skills
- 7 slash commands mapping to development lifecycle
- Automatic skill activation based on context
- Anti-rationalization tables in every skill
- Verification gates and exit criteria
- Agent personas (code-reviewer, test-engineer, security-auditor)
- Reference checklists for testing, security, performance, accessibility
- Support for Claude Code, Cursor, Gemini CLI, Windsurf, OpenCode, GitHub Copilot, Kiro
- Session lifecycle hooks
- MIT License - free to use and modify