LangGraph for RAG LangGraph models RAG as an explicit DAG/cyclic graph over a typed state. Unlike LCEL chains, it supports loops, branching, checkpointing, and HITL — exactly what agentic RAG needs. Installation Typed State uses a reducer so each node can append messages without clobbering prior turns. Without a reducer, each node overwrites the slot. Minimal Agentic RAG Graph CRAG (Corrective RAG) as LangGraph CRAG = retrieve → grade → if irrelevant, fall back to web search → generate. Self-RAG as LangGraph Self-RAG adds reflection tokens: , , , . Each becomes a node. Checkpointing (durable…