langgraph-fundamentals

Build stateful multi-turn agentic workflows by defining a StateGraph with nodes and edges. This approach provides fine-grained control over execution flow, state management, and conditional routing for complex agent orchestration.

State management in LangGraph uses state schemas and reducers to update application context. Developers define state structures that persist across multi-turn interactions, ensuring data flows correctly through the directed graph execution.

The best way to route execution conditionally in a LangGraph agent is using the Command API. It enables combined state updates and dynamic routing within the directed graph, allowing fine-grained orchestration of complex multi-step workflows.

Orchestrate parallel worker nodes in a LangGraph state graph using the Send API. This feature allows developers to dispatch multiple tasks simultaneously, enabling efficient parallel processing within stateful agentic workflows.

Implement error handling for LangGraph agents by configuring retry policies and tool error management strategies. This ensures stateful multi-turn workflows recover gracefully from execution failures within the directed graph orchestration.

Use a directed graph architecture for agent orchestration when your application requires complex conditional routing, fine-grained state management, and sequential or parallel execution steps that must maintain persistent context across multiple turns.