OpenAI debuts Codex CLI, an open source coding tool for terminals

OpenAI is introducing Codex CLI, a coding “agent” that can run locally from terminal software, as part of its effort to incorporate AI into more of the programming process.

Codex CLI, announced alongside OpenAI’s latest AI models o3 and o4-mini, connects OpenAI’s models with local code and computing tasks. This allows OpenAI’s models to write and edit code on a desktop and perform actions such as moving files.

While Codex CLI is a step towards OpenAI’s vision of agentic coding, it is not as advanced as the company’s plans for an “agentic software engineer” that can create and test apps based on project descriptions. However, Codex CLI does integrate OpenAI’s models with command-line interfaces and is open source.

According to an OpenAI spokesperson, Codex CLI is a lightweight coding agent that runs locally in the terminal, providing users with a transparent interface to link models directly with code and tasks. Users can benefit from multimodal reasoning by passing screenshots or sketches to the model while accessing their code locally through Codex CLI.

To encourage the use of Codex CLI, OpenAI plans to award $1 million in API grants to eligible software development projects, with $25,000 blocks of API credits given to selected projects.

It’s important to note that AI coding tools, including Codex CLI, come with risks such as potential security vulnerabilities and bugs. Users should exercise caution when giving AI access to sensitive files or projects.