descriptionstring nullable required
voiceMode'webhook' | 'hosted' required
modelTier'turbo' | 'balanced' | 'max' | 'realtime' | 'live'
systemPromptstring nullable
voicePromptstring nullable
beginMessagestring nullable
transferNumberstring nullable
customToolsobject[] nullable
voicemailMessagestring nullable
callScreeningIdentitystring nullable
callScreeningPurposestring nullable
sttMode'fast' | 'accurate'
Speech-to-text mode. 'fast' optimizes for latency, 'accurate' optimizes for transcription accuracy (~200ms additional latency).
ambientSound'none' | 'office' | 'coffee-shop' | 'outdoor'
Background ambience to mask synthetic silence between turns. 'none' disables; 'office', 'coffee-shop', 'outdoor' enable a quiet bed.
denoisingMode'noise-cancellation' | 'noise-and-background-speech-cancellation'
Audio denoising. 'noise-cancellation' (default) handles general noise. 'noise-and-background-speech-cancellation' is more aggressive for callers in cars, cafes, or near TVs.
maxSilenceMsinteger
Hang up the call after this many milliseconds of caller silence. Range 10000 (10s) to 3600000 (1 hour). Default 600000 (10 min).
voiceSpeednumber
Voice speed multiplier. Range 0.5 to 2.0. Default 1.0.
interruptionSensitivitynumber
How easily callers can interrupt the agent. Range 0.0 to 1.0. Default 0.8.
enableBackchannelboolean
When true, the agent interjects short filler words like 'uh-huh' or 'mhmm' during longer caller utterances. Defaults to true.
languagestring
BCP-47 locale that drives the agent's speech recognition and pronunciation. Defaults to 'en-US'.
createdAtstring date-time required