Use anthropic api and stream and handoff will have error

[Daose1997]

I used claude's model following the CUSTOM_MODEL_PROVIDER approach, as shown below

client = AsyncOpenAI(
    base_url="https://api.anthropic.com/v1/",
    api_key="sk-xxxxxxxxxxxxxxx-AAA",
)

class CustomModelProvider(ModelProvider):
    def get_model(self, model_name: str | None) -> Model:
        return OpenAIChatCompletionsModel(model="claude-3-5-haiku-20241022", openai_client=client)
        # return OpenAIChatCompletionsModel(model="claude-3-7-sonnet-20250219", openai_client=client)

CUSTOM_MODEL_PROVIDER = CustomModelProvider()


tracking_task_agent = Agent(
        name="team_leader",
        instructions=TRACKING_TASK_TEMPLATE.format(work_id=work_id),
        handoffs=[project_manager, architect, engineer],
        tools=[execute_mysql_sql],
    )

result = Runner.run_streamed(
            starting_agent=tracking_task_agent,
            input=first_input,
            context=context,
            max_turns=30,
            run_config=RunConfig(model_provider=CUSTOM_MODEL_PROVIDER)
        )

When I use Runner.run, the program runs normally and completes my entire workflow. When I use Runner.run_streamed, entering the handoff process, the API call returns the following error:
openai.BadRequestError: Error code: 400 - {'error': {'code': 'invalid_request_error', 'message': 'Failed to parse JSON: ', 'type': 'invalid_request_error', 'param': None}}

LLM The final output is

{
    "role": "assistant",
    "content": "\u6211\u5c06\u5e2e\u52a9\u60a8\u89c4\u5212\u8fd9\u4e2a\u7f51\u7ad9\u9879\u76ee\u3002\u9996\u5148\uff0c\u6211\u4f1a\u4f7f\u7528Eve\u4ee3\u7406\u6765\u8fdb\u884c\u9700\u6c42\u5206\u6790\u548c\u4ea7\u54c1\u8bbe\u8ba1\u3002",
    "tool_calls": [
      {
        "id": "toolu_01SnwkRUjwXYHygLL2uSy1gZ",
        "type": "function",
        "function": {
          "name": "transfer_to_eve",
          "arguments": ""
        }
      }
    ]
  },
  {
    "role": "tool",
    "tool_call_id": "toolu_01SnwkRUjwXYHygLL2uSy1gZ",
    "content": "{'assistant': 'Eve'}"
  }