Codex is Open Sourcing AI models

Back to Articles Codex is Open Sourcing AI models Published December 11, 2025 Update on GitHub Upvote 71 +65 ben burtenshaw burtenshaw Follow shaun smith evalstate Follow Building on our work to get Claude Code to train open source models, we are now getting Codex to go further. We gave Codex access to the Hugging Face Skills repository, which contains skills for Machine Learning and AI tasks such as training or evaluating models. With HF skills, a coding agent can: Fine-tune and apply RL alignment on language models Review, explain, and act on live training metrics from Trackio Evaluate checkpoints and act on evaluation results Create reports from experiments Export to and quantize models with GGUF for local deployment Publish models to the Hub This tutorial dives even deeper and shows you how it works and how to use it yourself. So let's get started. Codex uses AGENTS.md files to accomplish specialized tasks, whilst Claude Code uses 'Skills'. Fortunately, 'HF-skills' is compatible with both approaches and works with major coding agents like Claude Code, Codex, or Gemini CLI. With HF-skills, you can tell Codex something like: Fine-tune Qwen3-0.6B on the dataset open-r1/codeforces-cots And Codex will: Validate your dataset format Select appropriate hardware (t4-small for a 0.6B model) Use and update a training script with Trackio monitoring Submit the job to Hugging Face Jobs Report the job ID and estimated cost Check on progress when you ask Help you debug if something go...