Fine-Tune vs Prompt-Engineer an LLM: Decision Guide
Answer-first: A clear decision framework for AI engineers: when to fine-tune (LoRA/QLoRA), when to prompt-engineer, and when RAG is the right answer instead. Three engineers on the same team are trying to build the same thing: a customer support assistant that answers questions in the company’s specific support style, using terminology from their product documentation. One engineer says “just write a better system prompt.” Another says “we need to fine-tune a model.” The third says “this is clearly a RAG problem.” ...