Core Web Vitals
LCP, INP and CLS: what moves each one, and what only looks like it does.
Installation
$ npx skills add addyosmani/web-quality-skillsThe CLI's unit is the repository, so this installs everything in addyosmani/web-quality-skills, not core-web-vitals alone. It writes into whichever agent directories it finds — Claude Code, Codex, Cursor, Copilot, Windsurf, Zed.
Summary
LCP, INP and CLS: what moves each one, and what only looks like it does.
- Reach for it when a failing field-data report, where lab numbers are already green and unhelpful.
- Sits in Operate & maintain — production reality: debugging, performance, instrumentation, and writing down why the system is the way it is.
- Assumes web.
- Published by Addy Osmani. Well regarded, but not the vendor of the thing it covers.
- Installing pulls the whole addyosmani/web-quality-skills repository: this catalogue lists 1 other entry from it, and the repo may hold more.
Where it sits in delivery
Operate & maintainProduction reality: debugging, performance, instrumentation, and writing down why the system is the way it is.Everything in Operate →
The skill itself
The full text lives with its publisher and changes when they change it. Read it there rather than here — a mirrored copy of somebody else's procedure goes stale silently, and this page would have no way of telling you.
Related
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addyosmani/agent-skills - Deprecation & migrationRetiring an old path safely: migrating consumers, proving nothing still calls it, then deleting it.
addyosmani/agent-skills - Diagramming codeProduces accurate architecture and data-flow diagrams from the code that exists, not the code somebody described.
trailofbits/skills