R0054/2026-03-31/C002/SRC01/E01¶
Research-backed recommendation for 80/20 ratio of positive to negative instructions in AI prompts.
URL: https://www.vibesparking.com/en/blog/ai/prompt-engineering/2025-08-14-prompt-do-not-to-do-playbook/
Extract¶
Key findings from the search results summary:
- An empirical ratio of 80% positive to 20% negative instructions is recommended, "prioritizing positive guidance first by telling the AI what it should do"
- Research from KAIST found that "larger AI models actually perform worse on negated prompts — instructions telling them what not to do"
- Converting "don'ts" into "do's" is recommended: replace "don't write ungrammatical sentences" with "Self-check grammar and cohesion sentence by sentence and revise to fluency"
- "Models have systematic weaknesses in handling negation; positive instructions reduce ambiguity and off-topic drift"
- Despite this, negative constraints serve a distinct function: they establish hard boundaries that positive instructions cannot replicate
Relevance to Hypotheses¶
| Hypothesis | Relationship | Strength |
|---|---|---|
| H1 | Supports | Directly confirms that positive alone is insufficient — the 80/20 ratio implies both types are needed |
| H2 | N/A | Does not suggest constraints are merely helpful rather than necessary |
| H3 | Contradicts | Directly contradicts the idea that positive instructions alone suffice |
Context¶
The 80/20 ratio recommendation suggests that while positive instructions should dominate, negative constraints are a necessary complement — not optional. This aligns with the claim's assertion that positive instructions alone produced inconsistent results.