Skill Wiki
performance
Domain inferred from 11 atoms across the corpora.
Atom counts by kind
| Kind | Count |
|---|---|
| rule | 2 |
| anti-pattern | 1 |
| check | 1 |
| fact | 1 |
| feedback | 1 |
| metric | 1 |
| pattern | 1 |
| principle | 1 |
| term | 1 |
| tool | 1 |
Sample atoms
Blocking Third Party
Loading third-party JavaScript (analytics, ads, tag managers, marketing pixels, A/B testing snippets) synchronously in the <head> blocks the parser, delays First Contentful Paint, and exposes the page's performance to th…
Check Image Optimization
Validates image optimization: modern formats (webp/avif), responsive srcset, lazy-loading for below-fold, intrinsic width/height for CLS prevention, and decoded-byte-size proportional to displayed dimensions.
Rail Targets
Chrome's RAIL model (introduced 2015 by Paul Lewis & Paul Irish, reaffirmed in 2024 documentation) defines four perceptual budgets keyed to user activity: (1) RESPONSE — input acknowledgment within 100ms (Doherty thresho…
Feedback Perf Budget Rollout
Accumulated execution feedback from teams adopting Core Web Vitals performance budgets via @community/collection-performance-budget.…
Metric Inp Interaction To Next Paint
INP measures the latency from a discrete user input (click, tap, key press) to the next frame painted by the browser. Replaced FID (First Input Delay) as an official Core Web Vital in March 2024.…
Image Lcp Priority
Hint the browser that the LCP image is the most important resource on the page. Combines `<link rel='preload' as='image'>` with `fetchpriority='high'`, modern format negotiation, and explicit dimensions to drive sub-2.…
Perceived Vs Actual
Hard upper bounds for perception (RAIL model + Doherty threshold): user input MUST acknowledge within 100ms (button press feedback, focus ring, ripple); animation frames MUST commit within 16.…
Cls Budget
Set a CLS budget of 0.1 (Lighthouse synthetic, mobile preset). Block PRs whose budget regression is >0.05 above main. Track field CLS via RUM (web-vitals.js + analytics endpoint) and alert on rolling-p75 ≥ 0.…
Image Optimization
Every raster image in an HTML artifact MUST: (a) declare `loading='lazy'` for below-the-fold images, (b) be served in a next-gen format (WebP or AVIF) with a fallback, and (c) provide a `srcset` / `<picture>` for respons…
Inp
Interaction to Next Paint — a Core Web Vitals metric measuring the latency between a user input (click, tap, key press) and the next frame painted by the browser.…
Tool Web Vitals Js
Google's web-vitals.js library exposes the Core Web Vitals (LCP, INP, CLS) and supplemental metrics (FCP, TTFB) in a small, consistent API.…