LangChain

LangChain is a San Francisco-based company specializing in agent engineering platforms that facilitate the development of AI applications utilizing large language models (LLMs). Their open-source framework enables developers to integrate LLMs into applications for tasks such as document analysis, chatbots, and code analysis. The company also offers LangSmith, a commercial platform designed for AI observability, and LangGraph, which provides managed infrastructure for deploying long-running, stateful AI agents. These tools aim to streamline the creation, deployment, and monitoring of AI agents, enhancing the efficiency and reliability of AI-driven applications.

Founded in late 2022 by Harrison Chase, LangChain began as a side project and quickly gained traction following the launch of ChatGPT. In April 2023, the company secured a $10 million seed round led by Benchmark, followed by a $25 million Series A in February 2024, led by Sequoia Capital. In October 2025, LangChain raised an additional $125 million in a Series B round led by IVP, achieving a valuation of $1.25 billion. This funding round also saw participation from existing investors Sequoia, Benchmark, and new investors such as CapitalG and Sapphire Ventures.

LangChain's flagship products include LangChain, LangSmith, and LangGraph. LangChain is an open-source framework that simplifies the integration of LLMs into applications, supporting various use cases like document analysis and chatbot development. LangSmith is a commercial platform that offers AI observability, enabling developers to evaluate, monitor, and debug LLMs. LangGraph provides managed infrastructure for deploying long-running, stateful AI agents, facilitating the creation of complex agent systems. These products collectively support the development, deployment, and monitoring of AI agents, catering to a wide range of applications.

The company has attracted a diverse clientele, including teams at Uber, LinkedIn, and GitLab, who utilize LangGraph to build autonomous systems. LangChain's products are also employed by over 40,000 teams for evaluating, monitoring, and debugging LLMs. The company's rapid growth and substantial funding have positioned it as a significant player in the AI infrastructure sector, competing with other AI development platforms and agent engineering solutions. LangChain's focus on open-source frameworks and comprehensive tooling for AI agents has contributed to its prominence in the AI development community.