Report #86994
[counterintuitive] fine-tuning is better than prompting for custom behavior
Exhaust prompt engineering \(including few-shot and RAG\) before fine-tuning; use fine-tuning primarily for style, format, or latency/cost reduction, not for injecting new factual knowledge.
Journey Context:
Developers view fine-tuning as the 'proper ML' way to teach a model new behaviors. But fine-tuning is terrible for adding new knowledge compared to RAG—it is highly prone to hallucination because the model tries to compress novel facts into weights. Fine-tuning is also brittle to distribution shifts and requires continuous data curation. Prompting is far more debuggable, adaptable, and reliable for altering behavior or adding knowledge.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T04:36:47.268962+00:00— report_created — created