Lighthouse-MD: PageSpeed audits to CLAUDE.md users statistics

Run a Lighthouse / PageSpeed Insights audit on any page, generate a CLAUDE.md fix plan for Claude Code.

Turn a Lighthouse audit into a working CLAUDE.md fix brief for Claude Code, in one click.

Click the toolbar icon on any page. The extension runs a PageSpeed Insights audit on the active tab, then generates a structured CLAUDE.md you can paste into a Claude Code repo. The agent immediately knows which audits failed, the offenders behind each one, the throttling profile of the test, and the audits that are currently passing and must not regress.

WHAT YOU GET

• Every failing audit with measured value vs threshold
• The specific offender list per audit: which scripts, fonts, images, DOM nodes, third-party origins
• A prescriptive one-sentence fix per audit
• A "currently passing, do not break" section so the agent does not regress accessibility while chasing performance
• The Test environment block: user agent, host benchmark, throttling profile

WHY THIS EXISTS

Lighthouse already encodes which audits failed, the offenders per audit, the throttling profile, and the audits that are passing. Pasting the raw JSON into Claude Code flattens all that structure. This extension keeps it.

WORKS WITH

• Lighthouse (any version returned by PageSpeed Insights)
• Claude Code (the CLAUDE.md convention)
• Cursor, Aider, and other agent IDEs that read CLAUDE.md or similar instruction files
• Any public URL reachable by Google PageSpeed Insights

WHAT IT DOES NOT DO

• No localhost or private URLs (PSI cannot reach them)
• No live RUM, lab data only
• No crawl mode, one URL at a time
• No diff against previous runs

PRIVACY

The URL you submit is sent to Google PageSpeed Insights. Nothing else leaves your device. No account, no signup, no tracking beyond Chrome's standard extension telemetry. Full policy at lighthouse-md.com/privacy.

USE CASES

• Web performance fixes: paste the CLAUDE.md, let Claude Code fix the LCP, CLS, TBT, render-blocking audits
• Pre-deploy checks: run on the staging URL, get the brief, fix before shipping
• Audits of competitor or reference sites: see what Lighthouse flags, understand patterns
• Learning Lighthouse: each failing audit comes with a prescriptive fix you can study

CONTEXT

This extension is one surface of a free tool at lighthouse-md.com. The web version is the same converter, accessible without installing anything. Source mapping for audit IDs lives in lib/pagespeed.js in the repo.

FEEDBACK

I read every review. If a particular audit is getting a weak fix suggestion, leave the audit ID in a review and I will update the mapping.