GPT-5.3-Codex is OpenAI’s most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2. It achieves state-of-the-art results...
Specifications
- Provider
- OpenAI
- Type
- Vendor / proprietary
- Modality
- text+image+file->text
- Context window
- 400K
- Released
- February 24, 2026
Capabilities
Input: textInput: imageInput: fileOutput: textConfigurable reasoning effort
Strengths
include_reasoningmax_completion_tokensmax_tokensreasoningreasoning_effortresponse_formatseedstructured_outputstool_choicetools
