lcp

Chrome UX Report (CrUX) CLI Tool

Chrome extension (Manifest V3) that audits a page's images for technical SEO & performance issues - alt text, dimensions, file size, next-gen formats (WebP/AVIF), lazy loading, and LCP.

A plugin for Eleventy that adds a preload for the first image with fetchpriority="high"

Ultra-fast Speculative prefetching engine using native Speculation Rules, cursor trajectory prediction & history-based navigation. Instant.page-compatible drop-in. Zero dependencies.

Measure TTFB / LCP with throttle profiles, multi-tab parallel load, full-page screenshots, and TSV+ZIP export

Evidence-led Lighthouse, Core Web Vitals, bundle, image, and font audits for Claude Code.

State of Web Vitals MCP — free remote MCP for Core Web Vitals by CMS, CDN, and framework. No auth.

Browser extension overlaying the page's request waterfall with computed fetch priorities; flags render-blocking and late-discovered critical assets.

Codemod that adds fetchpriority and resource hints (preload/preconnect, lazy loading) across HTML, Next.js, Nuxt, and Astro templates.

Lint browser resource hints (preload/prefetch/preconnect) and fetchpriority in built HTML — scored, CI-ready, zero dependencies.

Diagnosis order and fix order for LCP, INP and CLS, organised around phase attribution rather than a list of tips. Eleven failing and corrected example pairs checked in CI, plus a field measurement script whose arithmetic is unit tested.