We gave Claude the ability to fine-tune language models using a new tool called Hugging Face Skills. Not just write training scripts, but to actually submit jobs to cloud GPUs, monitor progress, and push finished models to the Hugging Face Hub. With this skill, you can tell Claude things like:

1. Validate your dataset format
2. Select appropriate hardware (t4-small for a 0.6B model)
3. Use and update a training script with Trackio monitoring
4. Submit the job to Hugging Face Jobs
5. Report the job ID and estimated cost
6. Check on progress when you ask
7. Help you debug if something goes wrong

The model trains on Hugging Face GPUs while you do other things. When it’s done, your fine-tuned model appears on the Hub, ready to use. This isn’t a toy demo. The skill supports the same training methods used in production: supervised fine-tuning, direct preference optimization, and reinforcement learning with verifiable rewards. You can train models from 0.5B to 70B parameters, convert them to GGUF for local deployment, and run multi-stage pipelines that combine different techniques.

Full report : Hugging Face details how it used its new tool, Skills, to fine tune LLMs using Claude, including for writing scripts, submitting jobs to cloud GPUs, and more.