bright-sugar-29405
05/17/2026, 7:08 PMtall-airline-16756
05/17/2026, 7:08 PMtall-airline-16756
05/17/2026, 7:08 PMbright-sugar-29405
05/17/2026, 7:09 PMAgentSession(
llm=openai_plugin.LLM(
model="gpt-4.1-mini",
api_key=...,
),
tts=cartesia_plugin.TTS(
model="sonic-2",
api_version="2024-11-13", # sonic-3 uses "2025-04-16"
voice="c35946ea-f4b0-40fa-b1ba-1530d87b9c58",
api_key=...,
speed=None, # set per-call via tts_speed
emotion=None, # set per-call via tts_emotion
volume=None, # set per-call via tts_volume
sample_rate=22050, # voice trained at 22-24kHz; LK Cloud downsamples to 8k μ-law
),
stt=deepgram_plugin.STT(
model="nova-3",
api_key=...,
language="en",
interim_results=True,
endpointing_ms=100,
no_delay=True,
smart_format=True,
filler_words=False,
keyterm=[ # ~12 domain words — nova-3 keyterm prompting
"Evolv", "Talkstone", "Buyer's Choice",
"payment processing", "credit card processing",
"POS", "point of sale", "Heartland", "Square",
"Stripe", "PCI", "interchange",
],
sample_rate=8000,
),
turn_handling={
"turn_detection": <in-process LiveKit turn-detector ONNX>,
"endpointing": {
"min_delay": 0.4,
"max_delay": 0.8,
},
"interruption": {
"enabled": True,
"mode": "adaptive", # Adaptive Interruption Handling
"min_duration": 0.3,
"min_words": 2,
"resume_false_interruption": True,
"false_interruption_timeout": 0.5,
},
"preemptive_generation": {
"enabled": True,
"preemptive_tts": True,
},
},
vad=<silero.VAD loaded in prewarm>,
aec_warmup_duration=0.0,
)tall-airline-16756
05/17/2026, 7:09 PMgpt-4.1-mini can produce natural responses; tune prompts/system messages for friendly, consultative tone and brevity control if you want shorter replies.
• TTS: sonic-2 with that voice and 22k sample rate is fine. To be more conversational:
◦ Enable per-call tts_emotion and tts_speed to vary prosody (e.g., slight enthusiasm for upsell, calm for objections).
◦ Use natural pauses and sentence-level SSML (if supported) to avoid robotic pacing.
• STT (Deepgram nova-3): interim_results=True + no_delay=True supports low-latency turn detection, which helps flow. Keyterm list is good for domain accuracy.
• Turn handling:
◦ Turn detector ONNX + VAD means fast local turn decisions — good.
◦ Endpointing min_delay 0.4 / max_delay 0.8: these are short and will make the agent respond quickly; for more natural pacing consider slightly larger max_delay (e.g., 1.0s) so the agent doesn’t cut off brief thoughtful pauses.
◦ Interruption adaptive + resume_false_interruption True: this supports natural interruptions. Suggest increasing false_interruption_timeout to ~0.6–0.8s if you observe premature resumes.
◦ min_duration 0.3 and min_words 2 are reasonable to avoid reacting to short noises; lower them only if you need ultra-fast handoffs.
◦ Preemptive generation + preemptive_tts enabled: good for responsiveness. Ensure the LLM prompt accounts for possible mid-speech cutoffs to avoid half sentences.
• VAD & AEC: silero VAD and aec_warmup_duration=0.0:
◦ VAD is good; consider small AEC warmup (>0s) if echoes occur at session start.
◦ If participants use speakerphones, tune VAD thresholds to avoid false triggers.
Potential issues to watch for (test cases to run):
• Short pauses during the human’s thinking causing agent to interrupt—test with 0.5–1.0s pauses.
• Overlapping speech: verify how the system prioritizes human vs agent when STT interim + preemptive TTS triggers.
• False interruptions when brief background noises occur—adjust false_interruption_timeout and VAD sensitivity.
• Prosody monotony—test with varied tts_emotion values and confirm voice handles emotional cues.
Concrete next steps I can help with:
• Provide recommended numeric tweaks for endpointing/interruption based on your preferred conversational style.
• Draft system and user prompt examples for a warm, consultative sales tone.
• Suggest test scenarios and metrics to measure conversational naturalness (interruptions per call, latency, user satisfaction questions).
Which of the next steps would you like me to do now?
, with interactive elements