OpenAI released GPT-5.5, billed as its smartest and most intuitive model to use. The company emphasized agentic work capabilities: writing and debugging code, researching online, analyzing data, creating documents and spreadsheets, operating software, and moving across tools until a task is finished. It rolled out to Plus, Pro, Business, and Enterprise users in ChatGPT and Codex, with GPT-5.5 and GPT-5.5 Pro becoming available in the API the next day, April 24.