📄 中文摘要
开发者希望构建一个能够回答公司文档问题的聊天机器人，然而直接使用 OpenAI API 进行文档分块、嵌入生成、向量搜索、提示工程和记忆管理等操作需要耗费数周的时间。LangChain 是一个用于构建 LLM 应用的框架，提供了可组合的预构建组件，包括链、代理、RAG 和记忆等功能，能够简化开发流程。LangChain 的免费功能包括：将 LLM 调用组合成工作流的链、使用工具的 LLM 代理、增强检索生成的 RAG 管道、会话记忆管理以及支持多种格式的文档加载器。
LangChain 提供免费的 LLM 框架 — 使用链、代理和 RAG 构建 AI 应用
📄 English Summary
LangChain Has a Free LLM Framework — Build AI Applications with Chains, Agents, and RAG
A developer aimed to create a chatbot capable of answering questions about company documents, but the raw OpenAI API calls required for document chunking, embedding generation, vector search, prompt engineering, and memory management could take weeks of effort. LangChain is a framework designed for building LLM applications, providing pre-built components that can be easily combined, such as chains, agents, RAG, and memory. The free offerings of LangChain include: chains for composing LLM calls into workflows, agents that utilize tools, retrieval-augmented generation (RAG) pipelines, conversation memory management, and document loaders supporting various formats like PDF, CSV, HTML, and Notion.