What is web-quality-audit?

A comprehensive quality review based on Google Lighthouse audits, covering Performance, Accessibility, SEO, and Best Practices across 150+ checks.

How long does an audit take?

Duration depends on site size and complexity, but results are provided with actionable fixes and can be iterated quickly for small sites.

Can I automate this in CI/CD?

Yes. Integrate the audit into your CI/CD pipeline to detect regressions in performance, accessibility, SEO, and best practices.

web-quality-audit

npx machina-cli add skill addyosmani/web-quality-skills/web-quality-audit --openclaw

Files (1)

SKILL.md

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Web quality audit

Comprehensive quality review based on Google Lighthouse audits. Covers Performance, Accessibility, SEO, and Best Practices across 150+ checks.

How it works

Analyze the provided code/project for quality issues
Categorize findings by severity (Critical, High, Medium, Low)
Provide specific, actionable recommendations
Include code examples for fixes

Audit categories

Performance (40% of typical issues)

Core Web Vitals — Must pass for good page experience:

LCP (Largest Contentful Paint) < 2.5s. The largest visible element must render quickly. Optimize images, fonts, and server response time.
INP (Interaction to Next Paint) < 200ms. User interactions must feel instant. Reduce JavaScript execution time and break up long tasks.
CLS (Cumulative Layout Shift) < 0.1. Content must not jump around. Set explicit dimensions on images, embeds, and ads.

Resource Optimization:

Compress images. Use WebP/AVIF with fallbacks. Serve correctly sized images via srcset.
Minimize JavaScript. Remove unused code. Use code splitting. Defer non-critical scripts.
Optimize CSS. Extract critical CSS. Remove unused styles. Avoid @import.
Efficient fonts. Use font-display: swap. Preload critical fonts. Subset to needed characters.

Loading Strategy:

Preconnect to origins. Add <link rel="preconnect"> for third-party domains.
Preload critical assets. LCP images, fonts, and above-fold CSS.
Lazy load below-fold content. Images, iframes, and heavy components.
Cache effectively. Long cache TTLs for static assets. Immutable caching for hashed files.

Accessibility (30% of typical issues)

Perceivable:

Text alternatives. Every <img> has meaningful alt text. Decorative images use alt="".
Color contrast. Minimum 4.5:1 for normal text, 3:1 for large text (WCAG AA).
Don't rely on color alone. Use icons, patterns, or text alongside color indicators.
Captions and transcripts. Video has captions. Audio has transcripts.

Operable:

Keyboard accessible. All functionality available via keyboard. No keyboard traps.
Focus visible. Clear focus indicators on all interactive elements.
Skip links. Provide "Skip to main content" for keyboard users.
Sufficient time. Users can extend time limits. No auto-advancing content without controls.

Understandable:

Page language. Set lang attribute on <html>.
Consistent navigation. Same navigation structure across pages.
Error identification. Form errors clearly described and associated with fields.
Labels and instructions. All form inputs have associated labels.

Robust:

Valid HTML. No duplicate IDs. Properly nested elements.
ARIA used correctly. Prefer native elements. ARIA roles match behavior.
Name, role, value. Interactive elements have accessible names and correct roles.

SEO (15% of typical issues)

Crawlability:

Valid robots.txt. Doesn't block important resources.
XML sitemap. Lists all important pages. Submitted to Search Console.
Canonical URLs. Prevent duplicate content issues.
No noindex on important pages. Check meta robots and headers.

On-Page SEO:

Unique title tags. 50-60 characters. Primary keyword included.
Meta descriptions. 150-160 characters. Compelling and unique.
Heading hierarchy. Single <h1>. Logical heading structure.
Descriptive link text. Not "click here" or "read more".

Technical SEO:

Mobile-friendly. Responsive design. Tap targets ≥ 48px.
HTTPS. Secure connection required.
Fast loading. Performance directly impacts ranking.
Structured data. JSON-LD for rich snippets (Article, Product, FAQ, etc.).

Best practices (15% of typical issues)

Security:

HTTPS everywhere. No mixed content. HSTS enabled.
No vulnerable libraries. Keep dependencies updated.
CSP headers. Content Security Policy to prevent XSS.
No exposed source maps. In production builds.

Modern Standards:

No deprecated APIs. Replace document.write, synchronous XHR, etc.
Valid doctype. Use <!DOCTYPE html>.
Charset declared. <meta charset="UTF-8"> as first element in <head>.
No browser errors. Clean console. No CORS issues.

UX Patterns:

No intrusive interstitials. Especially on mobile.
Clear permission requests. Only ask when needed, with context.
No misleading buttons. Buttons do what they say.

Severity levels

Level	Description	Action
Critical	Security vulnerabilities, complete failures	Fix immediately
High	Core Web Vitals failures, major a11y barriers	Fix before launch
Medium	Performance opportunities, SEO improvements	Fix within sprint
Low	Minor optimizations, code quality	Fix when convenient

Audit output format

When performing an audit, structure findings as:

## Audit results

### Critical issues (X found)
- **[Category]** Issue description. File: `path/to/file.js:123`
  - **Impact:** Why this matters
  - **Fix:** Specific code change or recommendation

### High priority (X found)
...

### Summary
- Performance: X issues (Y critical)
- Accessibility: X issues (Y critical)
- SEO: X issues
- Best Practices: X issues

### Recommended priority
1. First fix this because...
2. Then address...
3. Finally optimize...

Quick checklist

Before every deploy

Weekly review

Check Search Console for issues
Review Core Web Vitals trends
Update dependencies
Test with screen reader

Monthly deep dive

Full Lighthouse audit
Performance profiling
Accessibility audit with real users
SEO keyword review

References

For detailed guidelines on specific areas:

Source

git clone https://github.com/addyosmani/web-quality-skills/blob/main/skills/web-quality-audit/SKILL.mdView on GitHub

Overview

A comprehensive web quality review modeled after Google Lighthouse, spanning Performance, Accessibility, SEO, and Best Practices. It analyzes 150+ checks and delivers actionable, code-ready recommendations.

How This Skill Works

It analyzes the provided project for quality issues, categorizes findings by severity, and returns concrete, actionable recommendations with code examples. The scope covers Performance, Accessibility, SEO, and Best Practices across 150+ checks.

When to Use It

You're auditing your site for quality and readiness.
You're reviewing web quality to meet standards.
You want to run a Lighthouse-style audit on a page.
You're checking page quality before a launch or update.
You're optimizing a website for performance, accessibility, and SEO.

Quick Start

Step 1: Provide the URL or project scope and start the audit.
Step 2: Review the Lighthouse-style findings and prioritize fixes.
Step 3: Implement the recommended fixes and re-run the audit to verify improvements.

Best Practices

Prioritize Critical and High issues first to maximize impact.
Couple findings with concrete code fixes and examples.
Validate fixes by re-running the audit to see score changes.
Use the output to drive targeted improvements in performance, accessibility, and SEO.
Integrate the audit into CI/CD to catch regressions early.

Example Use Cases

Auditing a marketing landing page to improve core metrics.
Evaluating a React SPA's performance and accessibility.
Integrating audits into CI to monitor nightly builds.
Optimizing a mobile ecommerce product page for speed.
Assessing blog pages with rich media and metadata.

Frequently Asked Questions

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