What it does
AI models can be unpredictable in how they format answers, which breaks programs that expect a specific structure. Outlines makes the model follow a chosen structure while it writes, instead of fixing mistakes afterwards.
A developer simply says what type of answer they want, such as yes or no, a number, or a form with set fields, and Outlines makes sure the reply matches. It works with many model providers, including OpenAI, Ollama and vLLM.
Who it's for
Developers who use AI output inside their software.
Can I use it without coding?
Developers only. A Python library. New to this? Start here.
Can I run it?
- Cost
- FreeNothing to pay or sign up for.
- Privacy
- Your choice: run it on your device or use an online service
- API key
- Not needed
Try it
Using Claude Code, Cursor or another AI coding assistant? Paste the prompt and it will walk you through the setup.New to this?
Before you install
- Only download from the official GitHub page. Copies with similar names exist for many popular projects.
- License (Apache-2.0): Permissive: free to use, change and share, including for business.
- More on staying safe