ArcFlow

Trace timeline (VS Code)

Inspect trace data policy execution traces as a chronological timeline in VS Code. Useful after failed runs, retry storms, or HITL interrupts.

Open trace timeline

  1. Export or save trace JSON as run-abc.arcflow.trace.json.
  2. Command palette: ArcFlow: View Trace Timeline (arcflow.viewTraceTimeline).
  3. Or open a *.arcflow.trace.json file and use the editor title timeline button.

Obtaining trace JSON

From server:

bash
curl -s "http://localhost:8080/v1/runs/RUN_ID/trace" \
 -H "Authorization: Bearer dev-secret" \
 > run.arcflow.trace.json

From CLI:

bash
arcflow trace RUN_ID --format json > run.arcflow.trace.json

Rename to *.arcflow.trace.json so VS Code activates the ArcFlow trace language mode.

Timeline content

Each event shows PascalCase kind and metadata fields only (trace data policy). Example sequence for a two-step linear workflow:

text
t+0ms WorkflowStarted step_count=2
t+12ms StepStarted step_id=...
t+45ms ProviderRequestSent provider=stub, input_tokens=10
t+48ms ProviderResponseReceived output_tokens=25
t+50ms StepCompleted
t+55ms StepStarted step_id=...
t+90ms StepCompleted
t+92ms WorkflowCompleted duration_ms=92

Failed run with retry:

text
t+0ms WorkflowStarted
t+20ms StepStarted
t+100ms ProviderError retryable=true
t+105ms RetryAttempted attempt=1
t+1200ms StepCompleted
t+1210ms WorkflowCompleted

HITL interrupt:

text
...
t+500ms WorkflowInterrupted approval_key=manager_signoff

No prompt text, tool arguments, or memory chunk content appears in the timeline.

TUI alternative

Terminal timeline without VS Code:

bash
arcflow trace RUN_ID --tui

Or fetch from server:

bash
arcflow trace RUN_ID --server http://localhost:8080 --tui

Field reference

Full event catalog: guides/observability/trace-event-reference.md.

Normative contract: Trace events (normative).

Related pages

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