Can't enable "LANGCHAIN_TRACING_V2" to do tracing in Hierarchical Agent Teams example

[timeff]

Hi, I am building the application using a hierarchical agent team. But when I enable the "LANGCHAIN_TRACING_V2" environment variable to send the data to the langsmith. I got the error

Error: Key team_members not found in channels
    at validateKeys (/Users/xxx/Lab/langchain-hierarchy-supervisor/node_modules/@langchain/langgraph/dist/pregel/validate.cjs:84:23)
    at CompiledStateGraph._defaults (/Users/xxx/Lab/langchain-hierarchy-supervisor/node_modules/@langchain/langgraph/dist/pregel/index.cjs:400:44)
    at CompiledStateGraph._streamIterator (/Users/xxx/Lab/langchain-hierarchy-supervisor/node_modules/@langchain/langgraph/dist/pregel/index.cjs:517:112)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5) {
  pregelTaskId: '2aa7cc38-a59e-5593-8b06-2b6963bc24fd'

At first, I thought it might be a problem with my application. But I created a new project and try copy and paste anything from the official tutorial at https://langchain-ai.github.io/langgraphjs/tutorials/multi_agent/hierarchical_agent_teams/. It turned out the same error happened again.

I can disable tracing by putting the environment variable to false but it will lose all of the tracing capability using langsmith.

[lemonps]

I have the same problem. Anyone know the solution?

[jacoblee93]

Very weird - will investigate!

[rpatel15-hue]

same issue for me, I wonder if it has to do with the way state is defined in the subgraphs