OpenAI Releases GPT-5.5, a Fully Retrained Agentic Model That Scores 82.7% on Terminal-Bench 2.0 and 84.9% on GDPval

OpenAI launched GPT-5.5, its most capable model yet and the first fully retrained base model since GPT-4.5.

The model is designed for more autonomous tool use and multi-step task completion, with a focus on coding and terminal workflows.

GPT-5.5 is rolling out to Plus, Pro, Business, and Enterprise users in ChatGPT and Codex.

It posted strong benchmark results, including 82.7% on Terminal-Bench 2.0 and 84.9% on GDPval.