# Startup Skills: Addy Osmani

> Every skill by Addy Osmani in the index, with a line saying when to use each one.

I index these, I do not host them. Every entry points at the original author's
repo and carries a source byline.

## Entries (9)

- [Browser testing with DevTools](https://github.com/addyosmani/agent-skills/tree/main/skills/browser-testing-with-devtools) by Addy Osmani: Use when a browser bug needs real DOM, console and network data via DevTools.
- [Code review and quality](https://github.com/addyosmani/agent-skills/tree/main/skills/code-review-and-quality) by Addy Osmani: Use when a change is about to enter the main branch unreviewed.
- [Constraint-driven development](https://github.com/addyosmani/agent-skills/tree/main/skills/constraint-driven-development) by Addy Osmani: Use when agents must not quietly lower a project's written quality bar.
- [Core Web Vitals](https://github.com/addyosmani/web-quality-skills/tree/main/skills/core-web-vitals) by Addy Osmani: Use when LCP, INP or CLS scores need improving from field and lab data.
- [Doubt-driven development](https://github.com/addyosmani/agent-skills/tree/main/skills/doubt-driven-development) by Addy Osmani: Use when high-stakes decisions need a fresh-context adversarial review before they stand.
- [Performance](https://github.com/addyosmani/web-quality-skills/tree/main/skills/performance) by Addy Osmani: Use when pages load slowly and the site needs to feel faster.
- [Security and hardening](https://github.com/addyosmani/agent-skills/tree/main/skills/security-and-hardening) by Addy Osmani: Use when code handling untrusted input, sessions or logins needs hardening against vulnerabilities.
- [Source-driven development](https://github.com/addyosmani/agent-skills/tree/main/skills/source-driven-development) by Addy Osmani: Use when an approach should be grounded in official documentation, not remembered patterns.
- [Web quality audit](https://github.com/addyosmani/web-quality-skills/tree/main/skills/web-quality-audit) by Addy Osmani: Use when a site needs one audit across performance, accessibility, SEO and best practices.

## Links

- [Page](https://startupskills.dev/addyosmani): the same list, for a person.
- [The whole index](https://startupskills.dev/llms.txt): all 189 entries.
- [Skills index](https://startupskills.dev/skills): every skill, with search.