Agent skill · data analytics · secondsky
web-performance-audit
Web performance audits with Core Web Vitals, bottleneck identification, optimization recommendations. Use for page load times, performance reviews, UX optimization, or encountering LCP, FID, CLS issues, resource blocking, render delays.
Why this skill is useful
Provides specific optimization strategies and executable scripts for performance audits that the AI wouldn't reliably generate on its own.
What it needs
Requires chrome-launcher, lighthouse installed locally. About 1k tokens when loaded. Last updated 2026-08-06. 204 stars on the source repository.
What this skill does
Web Performance Audit Conduct comprehensive performance audits and implement optimizations. Core Web Vitals Targets Metric Good Needs Improvement Poor -------- ------ ------------------- ------ LCP (Largest Contentful Paint) <2.5s 2.5-4s >4s FID (First Input Delay) <100ms 100-300ms >300ms CLS (Cumulative Layout Shift) <0.1 0.1-0.25 >0.25 INP (Interaction to Next Paint) <200ms 200-500ms >500ms Performance Measurement Lighthouse Automation Optimization Strategies Quick Wins (1-2 days) Enable gzip/brotli compression Minify CSS/JS Defer non-critical scripts Optimize images (WebP, lazy loading) Medium Effort (1-2 weeks) Implement code splitting Add service worker caching Preload critical resources Eliminate render-blocking resources Long-term (1-3 months) Architecture improvements CDN optimization Database query optimization Performance Budget Audit Checklist [ ] Measure baseline Core Web Vitals [ ] Run Lighthouse audit (mobile & desktop) [ ] Analyze real user metrics (RUM) [ ] Identify largest contentful element [ ] Check for layout shifts [ ] Review JavaScript bundle size [ ] Test on slow 3G connection [ ] Set performance budget [ ] Configure monitoring alerts
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills secondsky/web-performance-audit