I recently built a GitHub extension using ChatGPT Codex, and I wanted to share the prompts that I gave to Codex to build the tool. I thought about copy/pasting it out of the VSCode UI, but figured that the data must be available somewhere. It turns out that Codex stores sessions as .jsonl files in .codex/sessions. Looking through the session files, there’s a ton of data in there around what the LLM does, but I was only interested in messages that I sent. Fortunately each user message has type: user_message.