CLI reference

The CLI requires Node.js 22 or newer. Commands return 0 on success and 1 for validation errors, failed privacy findings, failed budgets, or operational errors.

studio

tracelens studio [--host 127.0.0.1] [--port 4173] [--store .tracelens/sourcemaps]

Starts the bundled Studio and its bounded in-memory collector. Keep the default loopback host. Browser collector requests are accepted only from loopback origins.

inspect

tracelens inspect trace.json

Prints the slowest captured interaction, timing segments, primary contributor, correlated network work, React renders, and long frames.

compare

tracelens compare BEFORE AFTER [--file trace.json] [--endpoint URL]

Reads a file or the running Studio collector and prints release, route, interaction, component, and long-frame deltas.

doctor

tracelens doctor

Checks the local Node version, package setup, release metadata, and source-map availability.

privacy audit

tracelens privacy audit [--file trace.json] [--endpoint URL]

Reports risky URL credentials, query strings, email-like values, sensitive keys, and unsafe metadata. Findings produce exit code 1.

sourcemaps upload

tracelens sourcemaps upload ./dist \
  --app dashboard \
  --release 1.0.0 \
  --url-prefix https://app.example/assets/ \
  [--repository https://github.com/OWNER/REPO] \
  [--commit SHA] \
  [--store .tracelens/sourcemaps]

Imports adjacent flat v3 maps into a local, release-scoped store. The command never uploads files to a remote service despite its compatibility-oriented name.

budget check

tracelens budget check \
  [--config tracelens.yml] \
  [--file trace.json] \
  [--endpoint URL] \
  [--release VERSION] \
  [--app NAME] \
  [--environment NAME] \
  [--format text|json]

Failed or insufficient-data checks produce exit code 1. JSON output follows budget report schema version 1.