LangChain handles linear pipelines. LangGraph handles everything that needs loops, branching, or persistent state. Here's the exact decision framework — with code showing when each breaks and why.
LangChain Explained: Build LLM Apps Without Boilerplate
LangChain is the most widely used framework for building applications on top of LLMs. This guide covers chains, prompt templates, output parsers, and LCEL — with real Python code snippets throughout.
