Ax vs Pydantic AI

Ax and Pydantic AI are both agent frameworks for Python. Ax is published by Ax and Pydantic AI by Pydantic. On GitHub, Pydantic AI has 20,838 stars and Ax has 2,969. Both were last active in Oct 2026. The table lines up where they differ (publisher, license, GitHub stars and weekly downloads) and has the install commands for both. Everything here comes from the listings' public sources and is refreshed daily. Ax describes itself as: DSPy-style toolkit for typed LLM signatures, agents and flows, TypeScript-first with Python, Java, C++, Go and Rust libraries. Pydantic AI: Typed Python SDK for building agents with swappable model providers, plus optional capabilities for memory, sub-agents, planning and durable execution. Licenses: Ax Apache-2.0, Pydantic AI MIT.