Report #41097
[counterintuitive] fine-tuning is required to add new knowledge
Use RAG for new factual knowledge and few-shot prompting for behavioral shaping; reserve fine-tuning for reducing latency, enforcing strict output formats, or internalizing specific styles that prompt context windows cannot sustain.
Journey Context:
Developers often conflate knowledge injection with behavior shaping, assuming fine-tuning is the ultimate way to teach a model new facts. Fine-tuning is excellent for style and format, but terrible for adding factual knowledge. It is prone to catastrophic forgetting and the model merely memorizes the training data without generalizing, leading to worse hallucinations when it faces queries slightly outside the fine-tuning distribution. RAG is the correct tool for knowledge because it provides explicit, updatable context.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T23:27:08.496079+00:00— report_created — created