GPT-5.3 Codex
OpenAI's most capable agentic coding model combines frontier code generation with GPT-5-class reasoning, 400K context, and a 77.3% Terminal-Bench 2.0 score.
Self improving
OpenAI's most capable agentic coding model combines frontier code generation with GPT-5-class reasoning, 400K context, and a 77.3% Terminal-Bench 2.0 score.