🚨 Before you build your first AI agent, learn these 3 fundamentals: LLMs, RAG, and Tool Use. Because if you don’t know how they connect you’re just building chaos with a fancy wrapper. Let’s break it down: 1. LLM (Large Language Model) This is the brain. It understands language, generates text, and reasons through problems. But it has no memory, no awareness, and no access to real data unless you give it one. On its own, it’s just a really smart parrot. 2. RAG (Retrieval-Augmented Generation) This is the memory + knowledge system. It helps your LLM pull in external information (like your docs, Notion, or product data). Without RAG, your agent “knows” nothing beyond its training cutoff. With it, it becomes context-aware. Think of RAG as the agent’s research assistant. 3. Tool Use This is the hands. Tool use allows your agent to actually take action run code, call APIs, send emails, update databases. Without tools, your agent can only talk. With tools, it can do. Now here’s how they connect: LLM = thinks RAG = remembers Tools = acts Put them together, and you have an intelligent system that can reason, recall, and execute. That’s what an AI agent actually is. Not just chat. Not just automation. But thinking automation that understands context, retrieves what it needs, and acts with purpose. Most people try to skip these fundamentals. Then wonder why their agents break, hallucinate, or go off the rails. Learn this stack. Master this loop. Everything else in AI builds on top of it.