CLI Reference: Replay Debugger

Commands for replaying and rolling back an agent's execution timeline.

The replay debugger merges an agent's audit log, observation log, and workspace snapshot history into a unified chronological timeline. See Replay Debugger for background.

ash replay timeline

Show the full merged execution timeline for an agent.

ash replay timeline <agent-id> \
  [--since <rfc3339>] \
  [--until <rfc3339>]
Argument/FlagDescription
agent-idTarget agent
--sinceOnly show events at or after this RFC3339 timestamp
--untilOnly show events at or before this RFC3339 timestamp

Example:

ash replay timeline <agent-id>

ash replay timeline <agent-id> \
  --since 2026-01-15T10:00:00Z \
  --until 2026-01-15T11:00:00Z

Timeline entry fields:

FieldDescription
timestampRFC3339 UTC
sourceaudit, observation, or snapshot
eventEvent type
detailEvent-specific detail

The timeline interleaves all three sources in strict chronological order, giving a complete picture of what the agent did, what it observed, and what its workspace looked like at each point.

ash replay rollback

Roll back an agent's workspace to a previous snapshot (replay-debugger shorthand).

ash replay rollback <agent-id> <index>

This is equivalent to ash workspace rollback but accessed through the replay interface. Use ash replay timeline to identify the snapshot index you want to restore.

Example workflow:

# 1. Review the timeline to find where things went wrong
ash replay timeline <agent-id>

# 2. Identify the snapshot index just before the bad action
# (snapshot entries appear inline in the timeline)

# 3. Roll back to that snapshot
ash replay rollback <agent-id> 3

Use cases

  • Root cause analysis: trace exactly what sequence of tool calls led to an undesired outcome.
  • Time-travel debugging: restore workspace state to any point and re-run with different inputs.
  • Compliance review: produce a complete audit-quality record of an agent's actions for a given time window.