How Tolan builds voice-first AI with GPT-5.1

Introducing GPT-Live

A new generation of voice models for natural human-AI interaction, now powering ChatGPT Voice.

Build more natural voice experiences with GPT‑Live‑1 in the API

GPT‑Live‑1 brings natural, full-duplex voice conversations to the API, with stronger instruction following, custom voices, and telephony support.

How we built a realtime system for responsive voice AI in six months

GPT-Live enables continuous voice interaction with AI, using a turnless speech model and low-latency architecture for faster, more natural conversations.

Advancing voice intelligence with new models in the API

Explore new realtime voice models in the OpenAI API that can reason, translate, and transcribe speech, enabling more natural and intelligent voice experiences.

Customizable, no-code voice agent automation with GPT-4o

Retell AI is transforming the call center with AI voice automation powered by GPT-4o and GPT-4. 1.

Introducing gpt-realtime and Realtime API updates

We’re releasing a more advanced speech-to-speech model and new API capabilities including MCP server support, image input, and SIP phone calling support.

GPT-5.3 Instant: Smoother, more useful everyday conversations

Conversation Coach: A Voice-enabled AI System that Helps Practice Difficult Workplace Conversations

Conversation Coach is a voice‑first AI system that lets managers rehearse difficult workplace conversations in a realistic spoken format. It tackles low‑latency interaction, adaptive bot personalities that simulate various employee types, and personalized feedback on content and policy compliance. The authors compare an end‑to‑end speech‑to‑speech model with a cascaded approach, finding the former offers lower latency and cost, while the cascaded model provides better reasoning for coaching quality, and they deployed the cascaded architecture to 40,000+ managers over six months.

How OpenAI delivers low-latency voice AI at scale

How OpenAI rebuilt its WebRTC stack to power real-time Voice AI with low latency, global scale, and seamless conversational turn-taking.

Gemini 3.1 Flash Live: Making audio AI more natural and reliable

Our latest voice model has improved precision and lower latency to make voice interactions more fluid, natural and precise.

Training Intelligent Voice Assistant Wakeup with Controllable Synthetic Conversations

The paper presents a new wake‑up system for voice assistants that goes beyond simple keyword spotting by adding contextual trigger detection. After the wake word is heard, the system reasons to differentiate between actual user commands and unrelated speech, enabling more efficient and context‑aware interactions. A data‑generation architecture is introduced that creates a 62.3‑hour corpus of controllable multi‑speaker conversations, including direct invocations, contextual follow‑ups, and non‑addressed speech, and experimental results confirm the approach’s effectiveness across varied synthetic scenarios.

GPT-5.1: A smarter, more conversational ChatGPT

We’re upgrading the GPT-5 series with warmer, more capable models and new ways to customize ChatGPT’s tone and style. GPT-5.