OpenAI upgrades GPT-5.5, as it plans to retire legacy ChatGPT models

OpenAI has upgraded GPT-5.5 Instant to respond more accurately with more natural, human-like language and shorter responses, while retiring older models like o3 (August 26) and GPT-4.5 (June 27) to focus resources on newer capabilities. The company is also adding a job search tool to ChatGPT that integrates with job boards like Indeed and Upwork to help users find positions and tailor resumes.