Description: I’m encountering a persistent InvalidUpdateError when attempting to update thread state in LangGraph API v0.4.20. The error occurs during state updates and suggests that a node named __copy__ doesn’t exist in my graph definition. This is happening with langgraph dev –allow-blocking and…

[image] Petar: Node hey @Petar - would it be possible to share a minimally reproducible example?

InvalidUpdateError: Node copy does not exist - LangGraph State Update Failure

Petar September 17, 2025, 11:10am 3

Fixed!

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