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playwright-trace

playwright-trace

github.com/microsoftTesting & quality98.8k46 installsUpdated today
Repository

About playwright-trace

Playwright Trace CLI is a command-line skill for inspecting Playwright test trace ZIPs without opening a browser. It helps developers investigate actions, network requests, console output, errors, and captured page state.

Key features

  1. 01Open and inspect trace metadata
  2. 02Filter and inspect test actions
  3. 03Review requests, console output, and errors
  4. 04Query DOM and accessibility snapshots
  5. 05List and extract attachments

Use cases

  1. 01Find the action that failed in a test
  2. 02Inspect requests associated with a test run
  3. 03Query a captured page without opening a browser

Install

Copy the command and run it in a terminal.

$npx skills add https://github.com/microsoft/playwright --skill playwright-trace

After installing, type/playwright-tracein Claude Code to confirm it loaded.

Details

From the project README

Playwright Trace CLI

Inspect .zip trace files produced by Playwright tests without opening a browser.

Workflow

  1. Start with trace open <trace.zip> to extract the trace and see its metadata.
  2. Use trace actions to see all actions with their action IDs.
  3. Use trace action <action-id> to drill into a specific action — see parameters, logs, source location, and available snapshots.
  4. Use trace requests, trace console, or trace errors for cross-cutting views.
  5. Use trace snapshot <action-id> to get the DOM snapshot, or run a browser command against it.
  6. Use trace close to remove the extracted trace data when done.

All commands after open operate on the currently opened trace — no need to pass the trace file again. Opening a new trace replaces the previous one.

Commands

Open a trace
# Extract trace and show metadata: browser, viewport, duration, action/error counts
npx playwright trace open <trace.zip>
Close a trace
# Remove extracted trace data
npx playwright trace close
Actions
# List all actions as a tree with action IDs and timing
npx playwright trace actions

# Filter by action title (regex, case-insensitive)
npx playwright trace actions --grep "click"

# Only failed actions
npx playwright trace actions --errors-only
Action details
# Show full details for one action: params, result, logs, source, snapshots
npx playwright trace action <action-id>

The action command displays available snapshot phases (before, action, after) and the exact command to extract them.

Requests
# All network requests: start time (on the `trace actions` clock), method, status, URL, duration, size
npx playwright trace requests

# Filter by URL pattern
npx playwright trace requests --grep "api"

# Filter by HTTP method
npx playwright trace requests --method POST

# Only failed requests (status >= 400)
npx playwright trace requests --failed
Request details
# Show full details for one request: headers, body, security
npx playwright trace request <request-id>
Console
# All console messages and stdout/stderr
npx playwright trace console

# Only errors
npx playwright trace console --errors-only

# Only browser console (no stdout/stderr)
npx playwright trace console --browser

# Only stdout/stderr (no browser console)
npx playwright trace console --stdio

# Filter by message text pattern
npx playwright trace console --grep "failed to fetch"
Errors
# All errors with stack traces and associated actions
npx playwright trace errors
Snapshots

The snapshot command loads the DOM snapshot for an action into a headless browser and runs a single browser command against it. Without a browser command, it returns the accessibility snapshot.

# Get the accessibility snapshot (default)
npx playwright trace snapshot <action-id>

# Use a specific phase
npx playwright trace snapshot <action-id> --phase before

# Run eval to query the DOM
npx playwright trace snapshot <action-id> -- eval "document.title"
npx playwright trace snapshot <action-id> -- eval "document.querySelector('#error').textContent"

# Eval on a specific element ref (from the snapshot)
npx playwright trace snapshot <action-id> -- eval "el => el.getAttribute('data-testid')" e5

# Take a screenshot of the snapshot
npx playwright trace snapshot <action-id> -- screenshot

# Redirect output to a file
npx playwright trace snapshot <action-id> -- eval "document.body.outerHTML" --filename=page.html
npx playwright trace snapshot <action-id> -- screenshot --filename=screenshot.png

Only three browser commands are useful on a frozen snapshot: snapshot, eval, and screenshot.

Attachments
# List all trace attachments
npx playwright trace attachments

# Extract an attachment by its number
npx playwright trace attachment 1
npx playwright trace attachment 1 -o out.png

Typical investigation

# 1. Open the trace and see what's inside
npx playwright trace open test-results/my-test/trace.zip

# 2. What actions ran?
npx playwright trace actions

# 3. Which action failed?
npx playwright trace actions --errors-only

# 4. What went wrong?
npx playwright trace action 12

# 5. What did the page look like at that moment?
npx playwright trace snapshot 12

# 6. Query the DOM for more detail
npx playwright trace snapshot 12 -- eval "document.querySelector('.error-message').textContent"

# 7. Any relevant network failures?
npx playwright trace requests --failed

# 8. Any console errors?
npx playwright trace console --errors-only

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