nexus/wiki/entities/LangChain.md

title, type, tags, sources, last_updated

title	type	tags	sources	last_updated
LangChain	entity	llm framework rag document-loading	RAG从入门到精通系列1：基础RAG	2026-04-16

Basic Information

• Type: LLM Application Framework
• Source: RAG从入门到精通系列1：基础RAG

Definition

LangChain is a framework for building LLM applications, providing over 160 different document loaders for loading data from various sources, as well as components for building RAG pipelines.

Key Features

• Document Loaders: 160+ loaders for various data sources
• Chain Abstraction: Link retrieval and generation components together
• Retriever Interface: Unified abstraction for retrieval components
• PromptTemplate: Template system for constructing prompts
• Integration: Works with various LLMs (Qwen, GPT-4, Claude, etc.) and vector databases (Qdrant, Chroma, Pinecone, etc.)

Applications in RAG

• Loading external documents via document loaders
• Splitting documents into chunks (Splits)
• Creating retrievers from vector stores
• Chaining retrieval and generation into a unified pipeline
• Converting raw AIMessage outputs to clean string results

Related Concepts

• RAG：LangChain is commonly used to build RAG pipelines
• LlamaIndex：Alternative framework for building LLM applications
• 向量数据库：Vector stores integrated with LangChain
• Qdrant：Vector database mentioned in RAG tutorials

Related Entities

• Qwen：LLM often used with LangChain