Thanks — I’m responding to your question about what a “UI Metrics report” is and how it relates to your stopwatch latency of 1.4 seconds.
Short answer
• “UI Metrics report” isn’t a formal LiveKit product name. The closest thing is the visual metrics you see in the LiveKit dashboards — primarily the
Agent Insights (Trace) view and the
Cloud Analytics dashboard — which break down end-to-end latency into component stages so you can understand where that 1.4s came from.
What those UI metrics show (how they relate to your 1.4s)
• Trace timelines show stage-by-stage durations such as:
◦ VAD detection / voice end detection
◦ STT (speech-to-text) processing
◦ LLM inference (time to first token)
◦ TTS synthesis and streaming (time to first audio bytes)
◦ Network/transport delays
• The dashboard reports metrics like Time To First Token (TTFT) and Time To First Byte (TTFB), which you can add together (plus VAD and network time) to explain your measured 1.4s.
How to verify and pinpoint the cause
1. Open the session in the LiveKit Cloud dashboard.
2. Go to
Agent Insights and open the
Trace view for the turn where you measured 1.4s.
3. Inspect the timestamps/durations for each stage (STT, LLM, TTS, etc.) and see which stage(s) sum to ~1.4s.
4. Optionally check Cloud Analytics for media-level metrics (bandwidth, packet loss, network latency) to rule out transport issues.
If you want, I can help next — tell me which of the following you prefer:
• I’d like step-by-step help reading a specific Trace entry (please share session/turn details).
• Show me how to find TTFT/TTFB in the dashboard.
• Help identifying whether STT, LLM, TTS, or network is the likely cause (I’ll need the Trace screenshots or timestamps).
Friendly tip: a stopwatch gives a good end-to-end number. The Trace view gives the breakdown so you can target the slowest component.
Sources:
Streamline troubleshooting with Agent Observability |
Streamline troubleshooting with Agent Observability |
Streamline troubleshooting with Agent Observability |
Agents (Python) | livekit/livekit_composite | DeepWiki |
How can I reduce latency in voice agents using STT, TTS and LLM? | LiveKit