OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI

Summary

OpenAI are quietly adopting skills, now available in ChatGPT and Codex CLI 12th December 2025 One of the things that most excited me about Anthropic’s new Skills mechanism back in October is how easy it looked for other platforms to implement. A skill is just a folder with a Markdown file and some optional extra resources and scripts, so any LLM tool with the ability to navigate and read from a filesystem should be capable of using them. It turns out OpenAI are doing exactly that, with skills support quietly showing up in both their Codex CLI tool and now also in ChatGPT itself. Skills in ChatGPT I learned about this from Elias Judin this morning. It turns out the Code Interpreter feature of ChatGPT now has a new /home/oai/skills folder which you can access simply by prompting: Create a zip file of /home/oai/skills I tried that myself and got back this zip file. Here’s a UI for exploring its content (more about that tool). So far they cover spreadsheets, docx and PDFs. Interestingly their chosen approach for PDFs and documents is to convert them to rendered per-page PNGs and then pass those through their vision-enabled GPT models, presumably to maintain information from layout and graphics that would be lost if they just ran text extraction. Elias shared copies in a GitHub repo. They look very similar to Anthropic’s implementation of the same kind of idea, currently published in their anthropics/skills repository. I tried it out by prompting: Create a PDF with a summary of the rimu tree situation right now and what it means for kakapo breeding season Sure enough, GPT-5.2 Thinking started with: Reading skill.md for PDF creation guidelines Then: Searching rimu mast and Kākāpō 2025 breeding status It took just over eleven minutes to produce this PDF, which was long enough that I had Claude Code for web build me a custom PDF viewing tool while I waited. Here’s ChatGPT’s PDF in that tool. (I am very excited about Kākāpō breeding season this year.) The reason it took so l...