Skill: Performance
SkillAI & modelsOptimize UI performance against Core Web Vitals — LCP, INP, CLS — with loading/code-split strategy, layout-shift prevention, and animation performance rules. Use when the user wants to improve speed, fix jank or layout shift, hit Web Vitals budgets, or make a UI feel fast on low-end devices.
Available today. Use it from your connected AI after setup.
No other account needed.
Connect ahel once, and every AI you use reads what you have installed.
Then ask your AI: use the Skill: Performance skill
What this skill tells your AI
The instructions your AI receives, as published by plugin87/ux-ui-agent-skills in .claude/skills/performance/SKILL.md and read by ahel’s review.
Make the UI fast and stable. Treat performance as an accessibility concern — slow/janky UIs fail low-end devices first.
Steps
- Read
workflows/performance.md(Core Web Vitals targets, loading strategy, layout-shift, animation perf, design-system runtime cost). - Diagnose against budgets: LCP ≤ 2.5s, INP ≤ 200ms, CLS ≤ 0.1. Measure on a mid-tier mobile profile (throttle slow 4G + 4× CPU).
- Loading: render above-fold first (SSR/Server Components), code-split by route + heavy widget, lazy-load below-fold/behind-interaction (Astro islands / Qwik), preload one critical font weight, modern responsive images.
- Kill layout shift: size skeletons to final dimensions, reserve media space via
aspect-ratio(tokens/sizing.json), never inject content above existing. - Animation: only
transform/opacity,will-changesparingly, 100–300ms (tokens/motion.json), honorprefers-reduced-motion. Prefer CSS state styling over JS for low INP; tree-shake/per-component imports.
Verification (definition of done)
- Lighthouse / field data meets LCP ≤ 2.5s, INP ≤ 200ms, CLS ≤ 0.1 on mid-tier mobile.
- First interaction stays responsive under slow-4G + 4× CPU throttle.
- Skeletons + media reserve space (zero CLS on load); no non-compositor animation in loops.
Signals
- GitHub stars
- 1k
- Forks
- 128
- Last commit
- Sep 2026
Advanced
- Catalog kind
- skill
- Gateway key
performance-plugin87- Source
- github.com/plugin87/ux-ui-agent-skills