"The vast majority of Codex is built by Codex," OpenAI told us about its new AI coding agent. In interviews with Ars Technica this week, OpenAI employees revealed the extent to which the company now relies on its own AI coding agent, Codex, to build and improve the development tool. "I think the vast majority of Codex is built by Codex, so it's almost entirely just being used to improve itself," said Alexander Embiricos, product lead for Codex at OpenAI, in a conversation on Tuesday.
Jules is intended as an 'asynchronous' coding agent, capable of working in the background alongside developers to write coding tests, fix bugs, and apply version updates across code. Users working with the agent can delegate complex coding tasks based on project goals, marking a contrast to manually-operated vibe coding models and AI coding assistants such as GitHub Copilot or Google Code Assist.