OpenAI Blog · Feb 5, 2026
GPT-5.3-Codex System Card
Reviewed by Errol Vogt, Site support technician & online learning analyst · original summary · editorial policy
GPT-5.3-Codex System Card. GPT‑5.3-Codex is the most capable agentic coding model to date, combining the frontier coding performance of GPT‑5.2-Codex with the reasoning and professional knowledge capabilities of GPT‑5.2. This update is relevant for small-office operators tracking changes in their tools.
Operator takeaway: For operators: review whether 'GPT-5.3-Codex System Card' affects your current setup before relying on it in production.