@livekit @LiveKit-Community @livekitteams @darryncampbell @CWilson @Muhammad_Usman_Bashir , @Akiniesta Hi LiveKit Team, We are observing that Time To First Token (ttft) is consistently logging as 0.0 ms when using the gemini-3.8-live model (via Vertex AI, location: ‘us’). Here is a sample metric l…

@Harshita_Sukumar_Patil , This is a plugin instrumentation issue in the Gemini realtime path, not your config; no agent or plugin option changes it. ttft is first_token_timestamp - created_timestamp ( realtime_api.py#L1611-L1613 ), and both anchors come from the server response stream: _created_timesta…

Issue: RealtimeModelMetrics.ttft is always logged as 0.0 for gemini 3.8 live on vertex ai

Agents

CWilson October 6, 2026, 3:08pm 2

Thanks for flagging. I will let the team know.

Gemini-3.8-live rejected with vertexai=True in livekit-plugins-google, although Vertex AI serves it (EU multi-region)

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Issue: RealtimeModelMetrics.ttft is always logged as 0.0 for gemini 3.8 live on vertex ai

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