Tracing

View, filter, replay, and export session traces for debugging and analysis.

Tracing

BAP automatically records NDJSON traces for every session to ~/.bap/traces/. The bap trace command lets you view, filter, replay, and export these traces.

View Recent Traces

bap trace                    # Last 10 steps from most recent session
bap trace --limit=20         # Last 20 steps
bap trace --all              # All steps

List Sessions

bap trace --sessions

Shows all recorded trace sessions with timestamps and step counts.

Filter by Session

bap trace --session=cli-9222

--session · string

Show traces for a specific session ID.

--limit · number · default: "10"

Number of trace entries to show.

--all · flag

Show all trace entries instead of the default last 10.

--sessions · flag

List all recorded trace sessions.

Replay as HTML Timeline

Generate a self-contained HTML timeline viewer:

bap trace --replay

Opens an interactive timeline showing every request with timing, status, and result summary. The HTML file is self-contained — no external dependencies.

--replay · flag

Generate a self-contained HTML timeline viewer and save it to the current directory.

Export as JSON

bap trace --export
bap trace --export=my-traces.json

--export · string

Export traces as JSON. Optionally provide a filename.

Trace Data

Each trace entry includes:

• Method — The BAP protocol method called (e.g., page/navigate, agent/act)
• Timing — Request start time and duration in milliseconds
• Status — Success or error
• Result summary — Condensed result data

Use bap trace to debug failures. Every BAP command is recorded with timing and result data, making it easy to identify what went wrong and when.