`OpenAIProvider` also accepts a custom`AsyncOpenAI` client via the`openai_client` parameter, so you can customise the`organization`,`project`,`base_url` etc. as defined in the[OpenAI API docs](https://platform.openai.com/docs/api-reference).

You could also use the[`AsyncAzureOpenAI`](https://learn.microsoft.com/en-us/azure/ai-services/openai/how-to/switching-endpoints) client to use the Azure OpenAI API.

```python {title="custom_openai_client.py"}

from openaiimport AsyncOpenAI

from pydantic_aiimport Agent

from pydantic_ai.models.openaiimport OpenAIModel

from pydantic_ai.providers.openaiimport OpenAIProvider

client= AsyncOpenAI(max_retries=3)

model= OpenAIModel('gpt-4o',provider=OpenAIProvider(openai_client=client))

agent= Agent(model)

You could also use the[`AsyncAzureOpenAI`](https://learn.microsoft.com/en-us/azure/ai-services/openai/how-to/switching-endpoints) client

to use the Azure OpenAI API. Note that the`AsyncAzureOpenAI` is a subclass of`AsyncOpenAI`.

from openaiimport AsyncAzureOpenAI