LangChain builds the frameworks and platforms that developers use to construct, test, and deploy AI agents and large language model (LLM) systems. Its open source offerings - the LangChain and LangGraph frameworks - together exceed 90 million downloads per month and connect to more than 1,000 integrations, making them among the most widely adopted tools in the agent engineering ecosystem. The company operates on an open-core model, pairing its open source frameworks with LangSmith, a commercial platform that adds observability, evaluation, and deployment capabilities for production LLM systems.
The open source frameworks provide pre-built architectures and developer tooling for assembling AI agents, while LangSmith addresses the reliability and monitoring demands that arise when those systems move into production. Together, the products cover the full development lifecycle - from early prototyping through to live deployment - targeting both the individual developer and the AI team operating at scale.
LangChain's user base spans major enterprises and early-stage startups alike, with millions of developers relying on its frameworks worldwide. The company is focused specifically on agent engineering: the discipline of building LLM-powered systems that can reason, plan, and act reliably in real-world environments.
