lighthouse-api

Use when running Lighthouse audits, performance testing, web vitals analysis, PageSpeed Insights API calls, or CI/CD performance monitoring. Also use when working with Core Web Vitals, accessibility audits, or LHCI.

Model	Source
sonnet	pack: google-apis

Full Reference

┏━ 🔧 lighthouse-api ━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓ ┃ Use when running Lighthouse audits, performanc… ┃ ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛

Lighthouse API

Google’s web auditing tool for performance, accessibility, SEO, and best practices. Available as CLI, Node.js module, PageSpeed Insights API, and Lighthouse CI (LHCI).

Current version: Lighthouse 13.0.x (Chrome 143, October 2025) · Requires Node.js 22.19 LTS

Quick Reference

Method	Best For
CLI	Local testing, scripting, one-off audits
Node.js API	Programmatic audits, custom flows, batch runs
PageSpeed Insights API	Remote testing without local Chrome, CrUX field data
LHCI	CI/CD regression prevention, historical tracking

Metric Weights (Performance Score)

Metric	Weight	Good
Total Blocking Time (TBT)	30%	< 200 ms
Largest Contentful Paint (LCP)	25%	< 2.5 s
Cumulative Layout Shift (CLS)	25%	< 0.1
First Contentful Paint (FCP)	10%	< 1.8 s
Speed Index (SI)	10%	< 3.4 s

---

Reference Index

File	What’s Inside
reference/running-audits.md	CLI flags, Node.js API, batch auditing, User Flows (Navigation / Timespan / Snapshot)
reference/performance-scoring.md	Metric weights, score ranges, Core Web Vitals (LCP / INP / CLS) thresholds + optimization
reference/pagespeed-insights-api.md	PSI endpoint, query params, rate limits, JS examples, response schema
reference/ci-integration.md	GitHub Actions workflows, performance budgets, LHCI config + commands + assertion syntax
reference/custom-config.md	Lighthouse config files, throttling presets, custom audit authoring, Lighthouse 13 renamed/removed audit IDs

Usage: Read the reference file matching your current task from the index above. Each file is self-contained with code examples and inline gotchas.