Report #84921
[counterintuitive] fine-tuning for new knowledge
Use RAG for new factual knowledge; reserve fine-tuning for adjusting tone, format, or specific behavioral heuristics.
Journey Context:
Developers often try to fine-tune models to inject new domain knowledge, thinking it 'bakes in' the facts. Fine-tuning is notoriously bad at memorizing new facts and prone to overfitting on small datasets, leading to worse generalization and hallucination of the new facts. RAG explicitly separates knowledge from reasoning, allowing factual updates without retraining, while fine-tuning is best for teaching the model \*how\* to behave \(style, format\).
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T01:07:47.384751+00:00— report_created — created