Augment the power of LLMs with your data
LangChain helps connect LLMs to your company’s private sources of data and APIs to create context-aware, reasoning applications.
The largest community building the future of LLM apps
LangChain’s flexible abstractions and AI-first toolkit make it the #1 choice for developers when building with GenAI.
LangChain keeps pace with the cutting edge, so you can too. Join 100k+ builders who standardize development in LangChain's Python and TypeScript frameworks.
A complete set of interoperable and interchangeable building blocks
Leverage our comprehensive library of components that together make up sophisticated, end-to-end applications. Want to change your model? Future-proof your application by making vendor optionality part of your LLM infrastructure design.
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Get customizability and control with a durable runtime baked in
LangChain Expression Language (LCEL) lets you build your app in a truly composable way, allowing you to customize it as you see fit. The protocol supports parallelization, fallbacks, batch, streaming, and async all out-of-the-box, freeing you to focus on what matters.
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Smart connections to any source of data or knowledge
Need turnkey observability?
LangSmith shines a light into application behavior and performance. Get prompt-level visibility coupled with tools to debug, test, evaluate, deploy, and monitor your applications with your team.
One framework. Infinite use cases.
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Ready to start shipping reliable GenAI apps faster?
LangChain and LangSmith are critical parts of the reference architecture to get you from prototype to production.