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chrome-devtools-mcp performance summaries include CrUX field data

Introduced 2026-02-10 · score 0.98

HOW TO USE IT

When reviewing a repository page’s performance, record a trace and inspect the stopped trace summary for CrUX field metrics alongside lab data. Set `--performance-crux=false` (or use `--no-performance-crux`) at server startup to disable sending trace URLs to the CrUX API.

navigate_page({"type":"url","url":"<repository-page-url>"})
performance_start_trace({"autoStop":false,"reload":false})
performance_stop_trace({})

WHY THIS HELPS

Review a performance trace for a repository page and compare lab metrics with real-user field metrics.

REQUIREMENTS AND LIMITATIONS

  • Version: 0.17.0
  • autoStop (required): Whether to stop the trace automatically.
  • reload (required): Whether to reload the selected page after tracing starts.
  • --performanceCrux / --performance-crux: Boolean; defaults to true. Set false to disable sending URLs from performance traces to the CrUX API for field data.
  • --no-performance-crux: Disable sending trace URLs to the CrUX API.
  • filePath: For start/stop trace tools, path to save raw trace data; may be absolute or relative to the working directory.
  • Prerequisite: Node.js v20.19 or newer maintenance LTS, Chrome current stable or newer, and npm.
  • Prerequisite: Navigate to the desired URL before starting a trace if `reload` or `autoStop` is true.
  • The server extracts primary navigation URLs from the trace, determined by insightSets.
  • It fetches field metrics for each unique URL or origin.
  • The `--performanceCrux`/`--performance-crux` boolean defaults to `true`.
  • Performance tools may send trace URLs to the Google CrUX API.

FIRST-PARTY EVIDENCE

Check the installed version and the source before using it. Entry JSON

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