Typescript bindings for langchain
npm install langchain!npm  
LangChain is a framework for building LLM-powered applications. It helps you chain together interoperable components and third-party integrations to simplify AI application development — all while future-proofing decisions as the underlying technology evolves.
Documentation: To learn more about LangChain, check out the docs.
If you're looking for more advanced customization or agent orchestration, check out LangGraph.js. our framework for building agents and controllable workflows.
> [!NOTE]
> Looking for the Python version? Check out LangChain.
To help you ship LangChain apps to production faster, check out LangSmith.
LangSmith is a unified developer platform for building, testing, and monitoring LLM applications.
You can use npm, pnpm, or yarn to install LangChain.js
``sh``
npm install -S langchainor
pnpm install langchainor
yarn add langchain
LangChain helps developers build applications powered by LLMs through a standard interface for agents, models, embeddings, vector stores, and more.
Use LangChain for:
- Real-time data augmentation. Easily connect LLMs to diverse data sources and external/internal systems, drawing from LangChain’s vast library of integrations with model providers, tools, vector stores, retrievers, and more.
- Model interoperability. Swap models in and out as your engineering team experiments to find the best choice for your application’s needs. As the industry frontier evolves, adapt quickly — LangChain’s abstractions keep you moving without losing momentum.
- LangSmith - Unified developer platform for building, testing, and monitoring LLM applications. With LangSmith, you can debug poor-performing LLM app runs, evaluate agent trajectories, gain visibility in production, and deploy agents with confidence.
- LangGraph - Build agents that can reliably handle complex tasks with LangGraph, our low-level agent orchestration framework. LangGraph offers customizable architecture, long-term memory, and human-in-the-loop workflows — and is trusted in production by companies like LinkedIn, Uber, Klarna, and GitLab.
- Deep Agents - Build sophisticated "deep" agents that go beyond simple tool-calling loops. Deep Agents combines planning tools, sub-agent spawning, file system access, and detailed prompts to handle complex, multi-step tasks — inspired by applications like Claude Code and Deep Research.
LangChain.js is written in TypeScript and can be used in:
- Node.js (ESM and CommonJS) - 20.x, 22.x, 24.x
- Cloudflare Workers
- Vercel / Next.js (Browser, Serverless and Edge functions)
- Supabase Edge Functions
- Browser
- Deno
- Bun
- Getting started: Installation, setting up the environment, simple examples
- Learn: Learn about the core concepts of LangChain.
- LangChain Forum: Connect with the community and share all of your technical questions, ideas, and feedback.
- Chat LangChain: Ask questions & chat with our documentation.
As an open-source project in a rapidly developing field, we are extremely open to contributions, whether it be in the form of a new feature, improved infrastructure, or better documentation.
For detailed information on how to contribute, see here.
Please report any security issues or concerns following our security guidelines.