addyosmani/agent-skills released: 25 production-grade engineering skills for AI coding agents

The project offers 25 skills spanning the full development lifecycle from define and plan to build, verify, review, and ship. Each skill includes steps, verification gates, and anti-rationalization tables. Nine slash commands (/spec, /plan, /build, /test, /review, /ship, etc.) map to the lifecycle and install as plugin commands in Claude Code; name collisions with built-ins require a namespace like /agent-skills:review. Skills can also auto-activate by task, e.g., api-and-interface-design when designing APIs or frontend-ui-engineering when building UI. After a plan is approved, /build auto-generates plans and implements all tasks test-first, pausing on failures or high-risk steps. Skills are plain Markdown, installable via npx skills into 70+ agents (Claude Code, Cursor, Codex, Copilot, Cline, and more), with native integrations per agent.