LangGraph Fundamentals

LangGraph state management requires defining state schemas with reducers to accumulate list values and apply custom merge logic, preventing partial state updates from overwriting existing data across nodes.

The Command API in LangGraph is used for combining state updates and conditional routing within graph edges, allowing you to simultaneously modify the graph state and direct the workflow to a specific node.

Set up conditional routing in a LangGraph StateGraph by defining conditional edges that evaluate the current state and return the name of the next node, or by using the Command API to dynamically route based on workflow logic.

LangGraph workflows fail on state list updates when reducers are missing from the state schema, so you must define annotated reducer functions to correctly accumulate and merge list data during partial state updates.

Yes, you can build an iterative document refinement agent in LangGraph by constructing a StateGraph with conditional edges that branch between editing and review nodes based on continuous feedback.

Yes, you must avoid mutable defaults when defining LangGraph state schemas to prevent shared state corruption, utilizing reducers and proper schema annotations for safe graph state initialization.