LangGraph is an open-source framework built on top of LangChain that enables developers to design and orchestrate complex workflows with large language models (LLMs). It introduces a graph-based architecture where nodes represent tools, functions, or model calls, and edges define the flow of information between them. This structure makes it easier to build multi-step, stateful AI applications such as agents, copilots, and reasoning systems. LangGraph supports features like branching, looping, memory, and error handling, allowing developers to create robust and reliable AI pipelines. Its tight integration with LangChain components, along with visualization tools like LangGraph Studio, helps teams debug, monitor, and optimize their workflows. With a focus on flexibility, composability, and transparency, LangGraph is well-suited for organizations building production-grade AI systems that require structured reasoning and orchestration.