# Pydantic AI vs OpenAI Agents SDK (Python)

## TL;DR

Both are code-first Python agent libraries under MIT. Pydantic AI centers on typed agents: validated outputs, dependency injection and provider-prefixed model strings, with durable execution integrations and AG-UI built in. The OpenAI Agents SDK centers on handoffs, guardrails, sessions and built-in tracing, and integrates most closely with OpenAI's hosted tools and Responses API.

## Facts side by side

|  | [Pydantic AI](https://multiagentguide.top/tools/pydantic-ai.md) | [OpenAI Agents SDK (Python)](https://multiagentguide.top/tools/openai-agents-sdk.md) |
| --- | --- | --- |
| Type | Framework | Framework |
| Languages / SDKs | Python | Python |
| License | MIT | MIT |
| Pricing model | [Open core](https://pydantic.dev/pricing) | [Open source, free](https://developers.openai.com/api/docs/pricing) |
| Orchestration pattern | Supervisor | Handoff |
| GitHub stars | 20,282 (as of 2026-09-30) | 29,784 (as of 2026-09-30) |
| GitHub forks | 2,831 | 4,837 |
| Last push | 2026-09-30 | 2026-09-30 |
| Latest release | v1.107.7 | v0.22.3 |
| Repository | [pydantic/pydantic-ai](https://github.com/pydantic/pydantic-ai) | [openai/openai-agents-python](https://github.com/openai/openai-agents-python) |
| Website | [pydantic.dev](https://pydantic.dev/pydantic-ai) | [openai.github.io](https://openai.github.io/openai-agents-python/) |
| Documentation | [pydantic.dev](https://pydantic.dev/docs/ai/) | [openai.github.io](https://openai.github.io/openai-agents-python/) |
| Last verified | 2026-09-30 | 2026-09-30 |
| MCP support | [Yes (checked 2026-09-30)](https://pydantic.dev/docs/ai/mcp/client/) | [Yes (checked 2026-09-30)](https://openai.github.io/openai-agents-python/mcp/) |
| A2A support | [Partial (checked 2026-09-30)](https://pydantic.dev/docs/ai/overview/interfaces/) | [No (checked 2026-09-30)](https://github.com/openai/openai-agents-python/issues/472#issuecomment-5192125355) |
| AG-UI support | [Yes (checked 2026-09-30)](https://pydantic.dev/docs/ai/integrations/ui/ag-ui/) | Unknown (checked 2026-09-30) |
| Install verified | 2026-09-30 | 2026-09-30 |

## Choose Pydantic AI if

- You want outputs and tool arguments validated by Pydantic and visible to type checkers.
- You need durable execution on Temporal, DBOS, Prefect, Restate or similar engines.
- You need AG-UI support in the package, or frequent switching between model providers by model string.

## Choose OpenAI Agents SDK (Python) if

- Your design is handoff-based: a triage agent passing the conversation to specialists.
- You want sessions with SQLite, Redis or SQLAlchemy backends and tracing included by default.
- You use OpenAI hosted tools, hosted MCP or sandbox agents.

## Migration notes

Agents map one to one: instructions, tools and an output type exist on both sides. Handoffs in the OpenAI SDK become either agent delegation through a tool or programmatic hand-off in application code in Pydantic AI; graph-style flows use the separate `pydantic-graph` package. Approvals move between `needs_approval=True` (OpenAI) and deferred tools with `requires_approval=True` (Pydantic AI). Conversation storage differs: the OpenAI SDK has session backends, while Pydantic AI expects you to serialize message history yourself or add the separate `pydantic-ai-harness` package. Version notes: Pydantic AI V2 is a breaking release with a migration map, and 1.x is still maintained in parallel; the OpenAI SDK is on 0.Y.Z versions where minor releases can break interfaces. A2A is not built into either: Pydantic AI points to the external `fasta2a` package, and OpenAI maintainers do not plan an SDK-owned A2A layer.

## FAQ

### Can Pydantic AI use OpenAI models and the OpenAI SDK use other models?

Yes to both. Pydantic AI selects providers with a model string; the OpenAI Agents SDK README states support for 100+ other LLMs besides OpenAI's APIs.

### Which has built-in tracing?

The OpenAI Agents SDK traces by default to OpenAI's dashboard or custom processors. Pydantic AI emits OpenTelemetry, which works with Logfire or any OTel backend.

### Which supports AG-UI?

Pydantic AI ships an AG-UI adapter. For the OpenAI Agents SDK no official AG-UI support was found; the cell is unknown.

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