If a user pauses briefly, and starts speaking afte...
# ask-aic
cool-lizard-26153
05/19/2026, 2:30 PMIf a user pauses briefly, and starts speaking after my agent is processing the user's request, will the second request have only the speech said after the agent started processing the request or will it append this new text to the previous said user text and send it in the request?
✅ 1
t
tall-airline-16756
05/19/2026, 2:30 PMThanks for reaching out, Bharath. I'm an AI assistant and I'm here to help. Give me a moment while I research this topic.
tall-airline-16756
05/19/2026, 2:31 PMThanks — I’m responding to your question about whether speech resumed after a brief pause is appended to the previous user text or sent as a new request.
Short answer: it depends.
• If the pause is shorter than the configured endpointing/silence threshold (VAD), or a model-based turn detector decides the turn is still active, the resumed speech is appended and sent as part of the same user turn.
• If the pause exceeds the endpointing threshold and the turn was already finalized for processing, the new speech becomes a separate user turn and is sent as a new request.
• Note: with preemptive generation the agent can begin processing a partial transcript; if turn detection later extends the turn, the full transcript (including speech after processing began) will be treated as one turn.
If you want, tell me your current endpointing settings (silence threshold) or whether you’re using model-based turn detection and I’ll help you pick values to match your UX goals.
Sources: Turns overview | LiveKit Documentation | Build Your First AI Voice Agent in Python: Complete Tutorial | LiveKit | Agent speech and audio | LiveKit Documentation | Turn Detection for Voice Agents: VAD, Endpointing, and Model-Based Detectio..., with interactive elements
c
cool-lizard-26153
05/19/2026, 2:35 PMI didn't enable any preemptive generation but I'm randomly seeing sometimes the text being appended, sometimes sent separately.
t
tall-airline-16756
05/19/2026, 2:36 PMThanks — I’m responding to your note that preemptive generation is off but you still see intermittent appending vs separate requests.
This inconsistent behavior is caused by turn-detection rules, not only preemptive generation. Key factors that make the system sometimes append and sometimes split turns:
• Voice activity detection (VAD) silence threshold: short pauses below the endpointing threshold are treated as the same turn and get appended; longer pauses pass the threshold and finalize the turn.
• Model-based turn detection (if enabled): it can extend or shorten endpointing based on semantic context, causing different outcomes for similar pauses.
• Audio timing variability: small differences in silence length, network jitter, or client-side buffering can change whether the pause crosses the threshold.
• Partial-processing timing: even without preemptive generation, the agent can begin processing as soon as it decides the turn ended; if subsequent audio arrives very shortly after, it may or may not be merged depending on the timing and the endpointing logic.
To narrow this down I can help further — please tell me:
• your current silence/endpointing setting (e.g.,
min_endpointing_delay