I’m running a graph with the architecture below, by which it should only execute the node get_product_id until a tool_condition calls it out of the React flow, and then it should go on with route_decision. But I’m getting an error: InvalidUpdateError("At key ‘route’: Can receive only one value per…

Solved! There was a double edge going from get_product_id to route_deceision, the conditional and a fixed one. I removed the fixed edge and now it works.

That was something in my head too :slight_smile: Great you have fixed that - good job! :slight_smile:

Graph execution goes back to a previous node

OSS Product Help LangGraph

pawel-twardziak October 1, 2025, 12:24pm 2

Hi @ignacio

could you share some more code? I have an idea why this might happen, but I need more details about how you have coded your agent.

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Graph execution goes back to a previous node

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