# Web Best Practices > Audits a website or web app against web-platform best practices and ships the fixes, across seven dimensions — semantic HTML + ARIA landmarks, accessibility, images/fonts, performance, security headers (CSP/HSTS), SEO metadata, and machine-readability for AI agents (llms.txt, schema.org JSON-LD, crawler access, Google's agent-ready rules). Runs a zero-dep static scanner over a project, guides the agent's semantic pass, and provides copy-paste fixes (llms.txt + security-header templates) plus authoritative sources (MDN, web.dev, W3C APG, llmstxt.org). Use when the user wants to check or improve a site's best practices, accessibility, security headers, CSP, semantic HTML, SEO/meta tags, structured data, schema.org, or make a site agent-ready or AI-crawler-friendly. For the deep Core Web Vitals CI gate (Lighthouse CI, CrUX), defer to web-perf-ci. - Skill: `yosefhayim/web-best-practices` (Agent Skill, multi-file: 7 files) - Install (CLI): `npx skillmds@latest add yosefhayim/web-best-practices` - Raw SKILL.md: https://api.skillmd.com/api/skills/yosefhayim/web-best-practices/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Marketing & Growth - Author: YosefHayim (https://skillmd.com/u/yosefhayim) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/yosefhayim/web-best-practices --- # Web Best Practices (audit + fix) One principle drives this skill: **making a site good for AI agents and good for humans is the same work.** Google's own agent guide says it — *"Everything we suggest to make a site 'agent-ready' also makes sites better for humans."* An agent reads a page through the screenshot, the raw DOM, and the **accessibility tree** — exactly what a screen reader, a search crawler, and a performance budget already reward. So this is **one audit**, scored across seven dimensions, each with a copy-paste fix. > **Perf is delegated.** This skill checks performance at a glance only; the measured Core Web Vitals CI gate (Lighthouse CI lab + CrUX field + web-vitals RUM) is the **`web-perf-ci`** skill — hand off there, don't re-implement it. ## The seven dimensions | # | Dimension | The bar | | --- | --- | --- | | 1 | **Semantic HTML & landmarks** | native elements over `
`; exactly one `
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` needs an accessible name or it isn't a landmark | | 2 | **Accessibility** | real `