LangGraph

LangGraph is a low-level orchestration framework from LangChain, Inc. for building stateful, controllable agents. Where a simple chain runs top to bottom, LangGraph models an agent's control flow as a StateGraph — nodes connected by direct and conditional edges, with cyclic execution, branching, and a typed state object that flows through every step. A checkpointer persists that state between steps, which is what enables durable execution, retries, human-in-the-loop pauses, and time-travel debugging of past runs.

This is the layer production teams reach for once an agent's logic stops being a straight line — multi-agent handoffs, loops, long-running workflows, and interventions that need to survive process restarts. As of late 2025, LangChain's own high-level create_agent API runs on top of LangGraph's execution engine, so LangGraph increasingly functions as the substrate beneath LangChain rather than a competing choice; it is equally usable standalone by teams who want the graph and state primitives without LangChain's higher-level abstractions. It ships as both a Python and a JavaScript/TypeScript library.

The core library is MIT-licensed and free, with no usage limits. LangChain also offers the LangGraph Platform, a managed runtime that adds a deployment server, one-click deploys, horizontally scaling task queues, and LangGraph Studio for visual debugging — priced separately for teams that want hosted, durable agent infrastructure rather than self-hosting the open-source runtime.