@simonwillison.net on Bluesky

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Simon Willison

simonwillison.net

did:plc:kft6lu4trxowqmter2b6vg6z

Wrote some notes on OpenAI codex, their new open CLI "agent" tool for writing and iterating on code. Since it's open source (Apache 2) the workings are available, including an interesting system prompt and a macOS sandbox using the sandbox-exec mechanism https://simonwillison.net/2025/Apr/16/openai-codex/

2025-04-16T22:10:05.685Z