Pydantic AI vs CrewAI
CrewAI models an agent system as a crew: roles, tasks and a process that runs them, with Flow for deterministic control flow around the crew and a large first-party tool package. Pydantic AI starts from a plain typed Agent and lets you pick the orchestration: sub-agents and delegation for a crew, pydantic-graph for a flow, and a Harness SDK of tools and capabilities.
Pydantic AI is one part of a stack: the Harness SDK for capabilities and complete agents, Pydantic Evals, Pydantic Graph, Pydantic Logfire for observability, and Pydantic itself for validation. The tables below cover the whole of it.
| CrewAI | Pydantic AI and Harness SDK | |
|---|---|---|
| Language | Python | Python |
| License | MIT | MIT |
| Model providers | Many | Many |
| Extensibility | Tools on agents and crews | Capabilities and toolsets; 50+ with the Harness SDK |
| Harnesses | Build your own | Built-in Coder and Researcher, or compose your own |
| Observability | OpenTelemetry | OpenTelemetry, including Pydantic Logfire |
| Durable execution | Yes | 5+ integrations |
| Interfaces | Enterprise UI, A2A | CLI, web chat, AG-UI, Vercel AI, ACP (experimental) |
| Realtime voice | No | Realtime |
| Evals | Yes | Pydantic Evals |
| Image generation | Yes | Image Generation |
| CrewAI | Pydantic AI and Harness SDK | |
|---|---|---|
| Multi-agent | Yes | Subagents, delegation, or pydantic-graph |
| Planning | Planner loop, no task list | Planning |
| Skills | Yes | Skills |
| Memory | Yes | Memory |
| Compaction | Yes | Compaction |
| Guardrails | Yes | Guardrails |
| Code sandboxes | Yes | Execution environments |
| Browser use | Yes | Web & research |