core-web-vitalslisted

# Core Web Vitals Measured LCP/INP/CLS diagnosis. From `addyosmani/web-quality-skills` `core-web-vitals`. ## When to use - LCP, INP, or CLS fail thresholds - User says "improve Core Web Vitals", "fix LCP", "reduce CLS" ## Workflow 1. **Measure** — Capture field (CrUX) + lab (Lighthouse, trace) at 75th percentile for LCP, INP, CLS. 2. **Diagnose** — For the failing metric: - LCP: critical rendering path, server response, render-blocking, image priority - INP: long tasks, main-thread blocking, hydration cost - CLS: layout shifts, font swapping, late-injected content 3. **Optimize** — One metric at a time, keep failures separate from hypotheses (see `performance` audit). 4. **Verify** — Re-measure at p75; confirm thresholds, no regression on other metrics. ## Verification - [ ] Baseline at p75 recorded for the failing metric - [ ] Diagnosis maps to metric-specific cause, not generic optimization - [ ] Fix applied to single metric, re-measured, thresholds met ## References - Source: `addyosmani/web-quality-skills` core-web-vitals