OpenAI makes GPT-Live-1 full-duplex voice model generally available in its API

Full duplex means the model can listen while speaking, which lets it handle interruptions and decide continuously whether to keep listening, pause, talk or call a tool. OpenAI's documentation says the model takes audio and text as input and output and can hand reasoning and tool work to a backend, either a model configured through the Responses API or any outside model or agent a developer connects. OpenAI's announcement also highlights stronger instruction following, custom voices and telephony support.

Developers reach the model through a dedicated Live sessions endpoint and can connect over WebRTC, WebSockets or SIP for phone calls. The documentation lists integrations with LiveKit, Twilio, Telnyx and Pipecat, and cautions that existing Realtime API integrations are not automatically compatible. Rate limits are counted in concurrent sessions, from 25 at the lowest paid tier to 500 at the highest, with no free tier.

OpenAI's benchmark figures, as reported by tbreak, put GPT-Live-1 at 80.1% on a full-duplex interactivity test, against 45.4% for GPT-Realtime-2.1, with turn-taking latency of 0.8 seconds versus 1.4. These are vendor numbers. Yelp is among early users, applying the model to phone-based reservations.