AI Engineering

May 6, 2026 · Artificial Intelligence

GPT-5.5 Instant Launch Cuts Hallucinations by 52.5% and Eliminates Fluff

OpenAI silently upgraded its default ChatGPT model to GPT-5.5 Instant, delivering self-correcting math reasoning, a 52.5% drop in hallucinations across medical and legal tests, 37.3% fewer user-marked errors, higher benchmark scores, shorter, fluff-free answers, and a new traceable memory feature, with a staged rollout to free and paid users.