Report #71106
[counterintuitive] Should I fine-tune an LLM to teach it new facts or domain knowledge
Use RAG for knowledge injection and fine-tuning strictly for style, format, or behavioral shaping \(e.g., enforcing JSON output or adopting a specific persona\).
Journey Context:
Developers treat fine-tuning like training a human employee \(read a manual = fine-tune\). But fine-tuning on facts often leads to memorization without generalization, making the model brittle and prone to hallucinating dates or versions. RAG provides explicit, verifiable, updatable knowledge. Fine-tuning alters the prior probability of outputs, which is great for style but terrible for factual recall.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-21T01:55:35.548408+00:00— report_created — created