TurnMetricsEvent

Defined in: src/core/events/types.ts:1134

Emitted once per conversation turn with the turn’s latency breakdown.

Remarks

Captures the timing of every pipeline stage for one turn — STT final → LLM first token → TTS first audio → playback start — as both absolute timestamps and derived durations. Use it to tune the eager pipeline (durations.sttFinalToFirstToken goes negative when a speculative generation was adopted) and to compare provider choices on real traffic.

Timestamps are epoch milliseconds, so each phase maps directly onto a tracing span (OpenTelemetry or otherwise) without clock translation.

Interrupted turns (barge-in, stopSpeaking(), pipeline errors) are also reported, with interrupted: true and whatever marks were captured before the interruption.

Example

agent.on('turn.metrics', (event) => {
  const { voiceToVoice, sttFinalToFirstToken } = event.durations;
  console.log(`turn ${event.turnId}: ${voiceToVoice}ms voice-to-voice`);
  if (event.eagerUsed) {
    console.log(`eager pipeline saved ${-sttFinalToFirstToken!}ms`);
  }
});

See

TurnMetricsSummary for field documentation

Extends

• BaseEvent.TurnMetricsSummary

Properties