Think of your LLM as a new hire at your company:
- Prompt engineering is how you give instructions: format, tone, constraints. Like writing your new hire a detailed brief before every assignment. It’s cheap, fast, and often enough. But you can’t instruct someone to know things they were never taught.
- Retrieval-Augmented Generation (RAG) is how you supply knowledge. You pull relevant documents from a database & feed them into the prompt, so the model stays “current” without retraining. Like handing your hire the company’s latest documentation before they answer a client.
- Agents are how you enable action. You give the model access to tools, APIs, and external systems, and then let it decide how to complete a goal. Like giving your hire access to the company’s CRM, email, and databases, then trusting them to pick the right tool.
- Fine-tuning is how you teach behavior. You train the model on curated examples of what you want it to do, and the change lasts. Like sending your hire through a specialized training program--they come back with a skill baked into how they work.
