OpenAI is pitching GPT-5.3-Codex as a long-running “agent,” not just a code helper: The company says the model combines GPT-5.2-Codex coding strength with GPT-5.2 reasoning and professional knowledge, ...

ChatGPT launched publicly on 30 November 2022 as a “research preview.” It was powered by GPT-3.5, marking the first time a powerful generative-pretrained transformer model was widely available in a ...