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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.
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 enables it to take on long-running tasks that involve research, tool use, and complex execution. Much like a colleague, you can steer and interact with GPT‑5.3‑Codex while it’s working, without losing context.