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LangChain

Open-source framework and platform for building reliable AI agents with LLMs.

Updated April 2026

Overview

Founded
2022
Headquarters
San Francisco, CA
Segment
Agent Frameworks & SDKs
Posture
Multi-Agent Frameworks

Product overview

LangChain builds open-source frameworks like LangChain, LangGraph, and deepagents for developing LLM-powered agents, alongside the LangSmith platform for observability, evaluation, and deployment. Used by thousands of companies including Klarna, ServiceNow, and 5 of the Fortune 10 for production AI agents in customer service, automation, and more. Distinct for its end-to-end agent engineering lifecycle support, from tracing/debugging to scalable deployment with human-in-the-loop and multi-agent orchestration.

Revenue model

Open-source core; LangSmith paid tiers: Developer (free, 5k traces/mo), Plus ($39/seat/mo, 10k traces/mo + pay-as-you-go), Enterprise (custom). Traces $2.50/1k base (14-day), $5/1k extended (400-day); additional deployment/Fleet usage fees.

Moat

LangChain's key competitive moat is its massive ecosystem of pre-built integrations, plugins, and chain templates that connect LLMs to hundreds of tools, databases, and services like OpenAI, Pinecone, and real-time data sources, drastically reducing development time and creating high switching costs for users reliant on its robust, customizable workflows. This is amplified by strong network effects from its large community, extensive documentation, and third-party contributions, making it the go-to framework for rapid AI agent deployment across industries like healthcare, finance, and retail.