[Why LangChain?](https://js.langchain.com/docs/concepts/why_langchain/): LLM should read this page when needing to understand LangChain's purpose, when evaluating if LangChain is suitable for an AI application, or when exploring LangChain ecosystem components. (This page explains why developers should use LangChain, highlighting its three main features: standardized component interfaces that make it easy to switch between providers, orchestration capabilities for complex applications through LangGraph, and observability/evaluation tools via LangSmith to monitor and improve applications.)

