LangChain is a framework for building applications that chain large language models with external data sources and third-party tools. It serves as an orchestrator for autonomous agents that use language models to plan and execute multi-step tasks, while providing a toolkit for linking interoperable AI components into sequences to prototype complex model behaviors.
The project provides a model agnostic integration layer, allowing users to switch between different language model providers using a standardized interface. It also includes tools for observability and evaluation to track the performance and reliability of deployed applications.
The framework covers a broad capability surface including retrieval augmented generation, workflow orchestration, and the creation of specialized agents. It further supports the deployment of stateful workflows and the monitoring of agent performance to debug operational issues.