LangGraph, released by LangChain in 2024, addresses a limitation the company's own earlier "chain" abstraction had: chains mostly moved data forward in a straight line, while real agent behavior needs to loop back, retry a failed step, or branch based on a decision, patterns that map more naturally to a graph than a straight sequence.
That graph-based structure, agent logic represented as nodes and edges, with explicit cycles allowed, gives developers more direct control over complex, stateful agent behavior than higher-level frameworks built for faster prototyping. It's positioned as the more production-grade option within LangChain's own ecosystem, for teams that have outgrown simpler chain-based approaches and need explicit state management.
The core library is free and open source, consistent with LangChain's broader tooling, with LangGraph Platform available separately for hosted deployment and monitoring. For a developer building an agent that needs loops, retries, and explicit state tracking rather than a straight-through sequence of steps, LangGraph's graph structure is built specifically for that more complex control flow.
