LangChain Has a Free API — Build AI Apps with Composable Chains

LangChain is the most popular framework for building AI-powered applications. It connects LLMs to tools, databases, and APIs with composable chains. What Is LangChain? LangChain provides abstractions for working with LLMs. Build RAG, agents, chatbots, and AI pipelines with reusable components. Features: LLM integration (OpenAI, Anthropic, Ollama, etc.) RAG (Retrieval Augmented Generation) Tool/function calling Memory management Streaming Free and open source Quick Start pip install langchain langchain-openai Python Examples from langchain_openai import ChatOpenAI from langchain.prompts import ChatPromptTemplate llm = ChatOpenAI ( model = " gpt-4o " ) # Simple chain prompt = ChatPromptTemplate . from_template ( " Explain {topic} in 3 sentences " ) chain = prompt | llm result = chain . invoke ({ " topic " : " Kubernetes " }) print ( result . content ) RAG Example from langchain_community.document_loaders import WebBaseLoader from langchain_openai import OpenAIEmbeddings from langchain_co