Prompting formula
The Positive Instruction + Negative Boundary formula
State what to do, then what NOT to do — the prompt-side twin of SD negative prompts.
Skeleton
Do: {desired}. Never: {forbidden}. If unsure, say 'insufficient context'. When to use it
Safety, style control, compliance.
How to apply it without breaking it
- Fill every slot. A formula with a missing slot silently degrades into a generic prompt — the model will fill the gap with its own assumptions.
- Keep the ordering. Structure carries meaning; moving the output contract to the front of a long prompt is the most common reason a good formula fails.
- Pin the output shape explicitly (format, length, delimiters) rather than describing it in prose.
- Test with three inputs: a typical one, an edge case, and one where the correct answer is "insufficient context".
Pairs well with
- Prompt templates — the formula is the frame, the template is the content.
- System prompts — where formulas become reusable products.
- Reasoning templates — for the reasoning-family formulas.