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OpenAI·Feb 5, 2026·v5.3·paid
GPT-5.3-Codex
GPT-5.3-Codex is OpenAI's most advanced agentic coding model, combining the coding performance of GPT-5.2-Codex with the reasoning and professional knowledge capabilities of GPT-5.2. It enables long-running tasks involving research, tool use, and complex execution, allowing interactive steering without losing context.
AI AgentsAgentic AICoding
overview
GPT-5.3-Codex is OpenAI's most advanced agentic coding model, combining the coding performance of GPT-5.2-Codex with the reasoning and professional knowledge capabilities of GPT-5.2. It enables long-running tasks involving research, tool use, and complex execution, allowing interactive steering without losing context.
key features
- 01Advanced agentic coding capabilities
- 02Enhanced reasoning and professional knowledge
- 03Supports long-running tasks with research and tool use
- 04Interactive steering without losing context
- 0525% faster than previous models
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