AIster · The agentic age · Products
OpenAI launches Codex CLI, then a Codex cloud agent
OpenAI entered the coding-agent race less than two months after Claude Code
Key facts
- Date
- 16 Apr 2025
- Era
- The agentic age
- Interest
- Products
- Threads
- Open vs closed, Agents, Labs & people
- Codex CLI
- 16 Apr 2025, open source (Apache-2.0)
- Codex cloud agent
- 16 May 2025, research preview in ChatGPT
- Model
- codex-1, a version of o3 tuned for software engineering
On 16 April 2025, alongside its o3 and o4-mini models, OpenAI open-sourced Codex CLI, publishing the code of a lightweight coding agent that runs in the terminal. On 16 May it launched Codex in ChatGPT, a cloud agent powered by codex-1, a version of o3, that works on coding tasks in a sandboxed computer in the cloud.
Sources
- OpenAI, Introducing OpenAI o3 and o4-mini, 2025-04-16
- TechCrunch, OpenAI launches Codex, an AI coding agent, in ChatGPT, 2025-05-16
- GitHub, openai/codex, 2026-10-01