OpenAI upgrades GPT-5.5 Instant model

OpenAI has updated the GPT-5.5 Instant version of ChatGPT and its API, while gradually phasing out the OpenAIo3 and GPT-4.5 models. This updated GPT-5.5 Instant model reduces hallucinations by 52.5% in high-risk subjects such as medicine, law, and finance.