dispatchCustomEvent() doesn't work properly in tool.

[leSullivan]

Hi im using a function Inside different Nodes of my Langgraph app to trigger a custom Event with dispatchCustomEvent().

I call this function after every tool call, but run into the error:

Error: Unable to dispatch a custom event without a parent run id. This function can only be called from within an existing run (e.g., inside a tool or a RunnableLambda).

Can someone help me with this problem ?

Code:

private async getDocuments(
    {
      query,
      reasoningStep,
    }: { query?: string; filter?: string; reasoningStep?: string },
    config: RunnableConfig,
  ) {
    if (!query) {
      throw new Error("Please provide the required 'query' property.");
    }

    this.streamReasoningStep(reasoningStep);
    .... 
}

async streamReasoningStep(reasoningStep: string) {
    if (!reasoningStep) {
      this.logger.warn('No reasoning step provided from', this.name);
      return;
    }

    await dispatchCustomEvent('onNewReasoningStep', {
      reasoningStep,
      agent: this.name,
    });
  }