streamEvents with Gemini 2.5 Pro returns an empty array

OSS Product Help LangChain
1

i’m using js version of langchain, and sometimes call gemini 2.5 pro model with streamEvents returns output empty array.

almost half of request is empty array.

im using this versions

{
  "dependencies": {
    "@langchain/core": "^0.3.72",
    "@langchain/google-common": "^0.2.16",
    "@langchain/google-genai": "^0.2.16",
  }
}

i checked google api response error log but it response success.

im try to use model gpt 4 and 5, claude, grok, gemini but it happens only gemin 2.5 pro.

and i try to same way call ‘stream’ it also returns output empty array .

this is how to call streamEvents.

  private createLangChainStreamEvent(param: CreateLangChainParam) {
    const agent = createToolCallingAgent({
      llm: param.llm,
      tools: param.tools,
      prompt: param.prompt,
    });

    const agentExecutor = new AgentExecutor({
      agent,
      tools: param.tools,
      maxIterations: 3,
    });

    // 임의로 들어간 값을 제거
    const cleanedData = Object.fromEntries(
      Object.entries(param.data).filter(
        ([, value]) => value !== undefined && value !== null,
      ),
    );

    const abortController: AbortController | undefined = isEmpty(param.signal)
      ? undefined
      : Array.isArray(param.signal)
        ? param.signal[0]
        : param.signal;
    return agentExecutor.streamEvents(cleanedData, {
      version: "v2",
      signal: abortController.signal,
    });
  }

what shoud i change this? or it just bug?