# Outlines vs PydanticAI — Fit & Features

Canonical: https://trutool.co/compare/outlines-vs-pydantic-ai
Author: Snehil (https://trutool.co/authors/snehil)

Compare Outlines and PydanticAI by use case, features, limitations, and evaluation questions.

## Compare fit, features, and limitations

### Outlines
Generate structured outputs from language models with schema constraints.
Best fit: Developers composing agents, structured model outputs, and tool workflows.
- Structured generation
- Schema constraints
- Model integrations
Before you choose: Check licensing, provider compatibility, maintenance, and tool permissions. Test failure recovery before enabling agent actions.
Pricing: https://dottxt-ai.github.io/outlines/latest/
- [Read Outlines profile](https://trutool.co/tools/outlines): Read Outlines profile

### PydanticAI
Python agent framework with typed outputs and dependency injection.
Best fit: Developers building and evaluating custom agents.
- Python agent framework with typed outputs and dependency injection
Before you choose: Check licensing, maintenance status, supported providers, and hosting or inference costs.
Pricing: https://ai.pydantic.dev/
- [Read PydanticAI profile](https://trutool.co/tools/pydantic-ai): Read PydanticAI profile