LangChain From Scratch — A Complete Beginner's Guide (with Diagrams)

This article provides an introduction to LangChain, a powerful open-source framework for building applications on top of large language models (LLMs) like GPT-4, Claude, and Gemini. It explains the user and builder perspectives on foundation models, and dives into the key components of LangChain.

Details

LangChain is an open-source framework that helps developers build applications on top of large language models (LLMs) like GPT-4, Claude, and Gemini. It provides modular components and end-to-end tools to simplify the process of creating complex AI applications such as chatbots, question-answering systems, and autonomous agents. The article explains the two perspectives people have when interacting with foundation models - the user perspective (using products like ChatGPT) and the builder perspective (building applications on top of these models). LangChain is a tool for the builder perspective, providing a unified interface to work with different LLM providers and their APIs. The key components of LangChain include Models, Prompts, Chains, Memory, Indexes, and Agents. These components work together to enable developers to build powerful LLM-based applications with ease. For example, the Models component provides a consistent API to interact with various LLMs, while the Chains component helps in orchestrating multiple steps in a workflow.