performance
Performance Skill
This skill ensures HTML pages are optimized for fast loading and good Core Web Vitals scores.
Core Web Vitals
The three metrics Google uses for page experience:
| Metric | Target | Measures |
|---|---|---|
| LCP (Largest Contentful Paint) | < 2.5s | Loading performance |
| INP (Interaction to Next Paint) | < 200ms | Interactivity |
| CLS (Cumulative Layout Shift) | < 0.1 | Visual stability |
Resource Hints
Preconnect (High Priority)
Establish early connections to critical third-party origins:
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