OpenAI adds SIP telephony to GPT-Live for inbound and outbound phone calls

OpenAI's GPT-Live voice model can now take and place phone calls through a SIP trunk. Developers keep call logic and credentials on their own servers, while the carrier and OpenAI handle the audio. OpenAI now lets developers connect phone calls to GPT-Live, its real-time voice model, through a SIP trunk. Developers can answer calls routed to their OpenAI project and place calls to phone numbers from their own systems. The setup, described in the OpenAI developer documentation on telephony and SIP, splits the work three ways. A SIP provider carries the phone network connection, OpenAI carries the call audio, and the developer's backend handles session settings, call controls, and business logic. The design puts most of the engineering burden on the developer's server.