Negative space prompt builder
Most prompt advice is about telling the model what to do. But a huge share of bad output comes from what the model does unasked — inventing facts, padding with filler, assuming a format, drifting off topic. Negative-space prompting names those boundaries explicitly. This builder turns your task description and the failure modes you have actually seen into a clean block of “do not” rules you can bolt onto any prompt.
How it works
You describe the task and list the mistakes the model keeps making. The builder combines your specific failure modes with a library of common ones — don’t fabricate, don’t assume missing context, don’t pad, don’t change scope, don’t add commentary — and assembles them into a single tight instruction block. It keeps the rules grouped and concise rather than sprawling, because a focused set of prohibitions guides the model far better than a long, vague one. The block is meant to sit after your positive instructions, bounding them.
Tips and notes
- Pair it with positive instructions. Negative space defines the edges; you still need to state the goal.
- Keep it to what bites. Five to ten real failure modes beat thirty hypothetical ones — over-prohibiting makes models timid.
- Name fabrication explicitly if accuracy matters. “Do not invent facts; say you don’t know” is one of the highest-value rules you can add.
- Iterate from real failures. The best negative-space rules come from outputs you have actually seen go wrong, not imagined ones.