# smolagents vs Pydantic AI

## TL;DR

smolagents is Hugging Face's small Apache-2.0 library whose `CodeAgent` writes each action as Python code, with manager agents calling managed sub-agents. Pydantic AI is a typed MIT framework: validated structured outputs, dependency injection, deferred tools and durable execution. Choose smolagents for code-acting agents and quick experiments; Pydantic AI for typed application code.

## Facts side by side

|  | [smolagents](https://multiagentguide.top/tools/smolagents.md) | [Pydantic AI](https://multiagentguide.top/tools/pydantic-ai.md) |
| --- | --- | --- |
| Type | Framework | Framework |
| Languages / SDKs | Python | Python |
| License | Apache-2.0 | MIT |
| Pricing model | Open source, free | [Open core](https://pydantic.dev/pricing) |
| Orchestration pattern | Supervisor | Supervisor |
| GitHub stars | 29,604 (as of 2026-09-30) | 20,282 (as of 2026-09-30) |
| GitHub forks | 3,015 | 2,831 |
| Last push | 2026-09-30 | 2026-09-30 |
| Latest release | v1.26.0 | v1.107.7 |
| Repository | [huggingface/smolagents](https://github.com/huggingface/smolagents) | [pydantic/pydantic-ai](https://github.com/pydantic/pydantic-ai) |
| Website | [huggingface.co](https://huggingface.co/docs/smolagents) | [pydantic.dev](https://pydantic.dev/pydantic-ai) |
| Documentation | [huggingface.co](https://huggingface.co/docs/smolagents/index) | [pydantic.dev](https://pydantic.dev/docs/ai/) |
| Last verified | 2026-09-30 | 2026-09-30 |
| MCP support | [Yes (checked 2026-09-30)](https://huggingface.co/docs/smolagents/tutorials/tools) | [Yes (checked 2026-09-30)](https://pydantic.dev/docs/ai/mcp/client/) |
| A2A support | Unknown (checked 2026-09-30) | [Partial (checked 2026-09-30)](https://pydantic.dev/docs/ai/overview/interfaces/) |
| AG-UI support | Unknown (checked 2026-09-30) | [Yes (checked 2026-09-30)](https://pydantic.dev/docs/ai/integrations/ui/ag-ui/) |
| Install verified | 2026-09-30 | 2026-09-30 |

## Choose smolagents if

- You want agents that act by writing Python code, executed in a Blaxel, E2B, Modal or Docker sandbox.
- You want a small core you can read; the README states the main agent logic is under 1,000 lines.
- You want to share agents and tools through the Hugging Face Hub or a Gradio UI.

## Choose Pydantic AI if

- You need validated, typed outputs and tool arguments.
- You need tool approval that survives the process (deferred tools) or durable execution on an external engine.
- You need AG-UI support, which has no documented counterpart in smolagents.

## Migration notes

A smolagents `ToolCallingAgent` maps closely to a Pydantic AI `Agent` with tools. A `CodeAgent` has no direct equivalent: in Pydantic AI the model calls typed tools instead of writing code, so logic that lived in generated Python must become tools. `managed_agents` hierarchies become agent delegation through tools. Human review moves from `step_callbacks` on planning steps to deferred tools with `requires_approval=True`. Known limits to check before relying on smolagents multi-agent setups: snippet-level sandboxing (`executor_type`) does not support multi-agent setups per its secure execution guide, and open issues report problems with two-level managed-agent hierarchies and shared state in parallel runs. The built-in local Python executor is documented as not being a security boundary.

## FAQ

### What is a code agent?

In smolagents, a `CodeAgent` expresses each step as a Python snippet that the framework executes, instead of emitting a JSON tool call. `ToolCallingAgent` is the JSON-tool-call alternative.

### Do both support MCP?

Yes. Both document MCP client support. A2A is unknown for smolagents and partial for Pydantic AI (through the external `fasta2a` package).

### Are both free?

smolagents is Apache-2.0 with no paid product attached to it. Pydantic AI is MIT; Pydantic sells Logfire and enterprise support, neither required.

---

Data as of 2026-09-30. Not affiliated with listed projects. HTML version: https://multiagentguide.top/compare/smolagents-vs-pydantic-ai