Codex

Codex is a cloud-based software engineering agent that can answer questions about a codebase, run commands and tests in an isolated sandbox, and propose changes as draft pull requests. It aims to streamline code generation, refactoring, and debugging by working with real repositories and surfacing verifiable artifacts like logs and test results.

Codex is available in ChatGPT and also in an open-source terminal app called Codex CLI for local workflows.

It allows you to provide an AGENTS.md file to guide behavior and environment setup. It uses engineering-tuned models and agent scaffolding.

Official website: openai.com/codex