FaceTime Audio vs. Video - Chert

FaceTime Video supports audio and video in both directions: your agent can hear and see the caller, and the caller can hear and see your agent. FaceTime Audio carries audio only.

Outbound BYOR currently supports audio only on enabled lines. The video guidance below applies to enabled inbound video calls. See Outbound.

Media comparison

	FaceTime Video	FaceTime Audio
Avatar	Animated persona or participant video	No video track; voice only
Connecting experience	Branded holding screen for ~5–10 seconds	Silence during initialization; holding audio is planned
Assistant config	Same assistant; avatar is rendered	Same assistant; avatar_id is unused
Sessions	Audio and video in both directions	Audio in both directions
Call record	`media: { audio: true, video: true }`	`media: { audio: true, video: false }`

Practical guidance

For coaching and movement analysis, connect the caller’s video frames to your own vision pipeline. Media transport supplies the track; your agent supplies the perception and coaching behavior. Use BYOR with your own agent, even when Chert operates the FaceTime line.

Keep greetings concise. For outbound, wait for bridge_ready or the corresponding outbound call.started notification before speaking.
Inbound audio and video use the incoming-decision webhook. Outbound audio starts with an API request.
During design-partner rollout, call.incoming includes media, allowing different accept or decline logic by call type.

For BYOR, subscribe to the bridge participant’s facetime-remote-audio and facetime-remote-video tracks. Handle camera mute and track changes throughout the call.