LangChain
Also known as: LangChain.js, LangChain Python
In one sentence
An open-source framework for building applications with LLMs, providing tools for chaining prompts, managing memory, connecting to external tools, and building AI agents.
Explain like I'm 12
Like LEGO blocks for AI apps—it gives you pre-built pieces (prompt templates, memory, tools) that snap together to create chatbots, research assistants, and other AI-powered software.
In context
LangChain simplifies complex AI workflows. Instead of manually coding prompt chains and tool integrations, you use LangChain's components: chains (sequences of LLM calls), agents (LLMs that decide which tools to use), memory (conversation history), and retrievers (for RAG systems).
See also
Related Guides
Learn more about LangChain in these guides:
Orchestration Options: LangChain, LlamaIndex, and Beyond
IntermediateFrameworks for building AI workflows. Compare LangChain, LlamaIndex, Haystack, and custom solutions.
12 min readAI Workflows and Pipelines: Orchestrating Complex Tasks
IntermediateChain multiple AI steps together into workflows. Learn orchestration patterns, error handling, and tools for building AI pipelines.
7 min readAgents & Tools: What They're Good For (and What to Watch For)
IntermediateUnderstand AI agents that use tools to complete tasks. When they work, when they fail, and how to use them safely.
10 min read