GPT-5-Codex is a specialized variant of OpenAI’s GPT-5 family designed for complex software engineering workflows: coding, large-scale refactoring, long multi-step agentic tasks, and extended autonomous runs inside the Codex environment (CLI, IDE extension, and cloud). It is positioned as the default model for OpenAI’s Codex product and is accessible via the Responses API and Codex subscriptions.
Model Type: Code
GPT-5-Codex is OpenAI’s new, engineering-focused variant of GPT-5, tuned specifically for agentic software engineering inside the Codex product family. It’s designed to take on large real-world engineering workflows: creating full projects from scratch, adding features and tests, debugging, refactors, and performing code reviews while interacting with external tools and test suites. This release represents a […]
September 15, 2025. OpenAI unveiled GPT-5-Codex, a specialized variant of GPT-5 optimized for agentic software engineering inside its Codex product. The company says the model can operate autonomously on large, complex engineering tasks for more than seven hours at a stretch, iterating on implementations, fixing failing tests, and delivering completed work with reduced human intervention. […]
