Fine-Tuning vs RAG: They Solve Different Problems

The comparison is usually framed as a cost or accuracy trade-off. It is not. Retrieval and fine-tuning change different things, and the useful question is which thing is broken. The one distinction that matters Retrieval changes the context . At inference time, something outside the model finds relevant text and puts it in the prompt. The weights are untouched, the facts are current as of the last index refresh, and you can point at exactly which document produced the answer. Fine-tuning…