Both sit in the framework layer with similar commercial terms, so the practical split is language: Mastra targets TypeScript and Pydantic AI targets Python.
TypeScript agent framework with workflows, memory, evals and a local playground.
Type-safe Python agents with structured output that actually validates.
| Mastra | Pydantic AI | |
|---|---|---|
| Licence | Open source | Open source |
| Pricing | open source | open source |
| Self-hostable | Yes | Yes |
| Languages | TypeScript | Python |
| Install | npm install @mastra/core | pip install pydantic-ai |
| Keys required | None | None |
Both sit in the framework layer with similar commercial terms, so the practical split is language: Mastra targets TypeScript and Pydantic AI targets Python. Mastra: TypeScript agent framework with workflows, memory, evals and a local playground. Pydantic AI: Type-safe Python agents with structured output that actually validates.
Mastra can run on your own infrastructure. Pydantic AI can run on your own infrastructure.
Mastra is open source (open source). Pydantic AI is open source (open source).
Every page here answers to Accept: text/markdown and returns the same content at roughly a tenth the tokens. No separate site, no toggle — same URL.
curl -s -H "Accept: text/markdown" https://newagent.build/compare/mastra-vs-pydantic-ai