Prompt Laboratory
See why a small wording change flips model behavior, by comparing prompt structures side by side.
- Sample workflow
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Version A 0 tokens
Version B 0 tokens
Findings
Detected by local pattern analysis. Select a finding to highlight the exact text it refers to.
Idle
Prompt anatomy
Where the prompt spends its budget.
Idle
Side by side diff
Word level difference from version A to version B.
Idle
Improved draft
A rule based rewrite of version A. Every change is listed with its reason.
Idle
This is not a model rewrite
These edits come from the same local rules that produced the findings above. Where a fix needs your judgment, the draft inserts a bracketed marker rather than inventing a requirement you never stated.Note Why does a small wording change alter behavior?
A prompt is not read as prose. Every clause either narrows the space of acceptable answers or leaves it open. A word like appropriate does not narrow anything, so the model fills the gap from its own priors, and those priors shift between versions, temperatures, and even reorderings of your text.
The findings above are the places where your prompt leaves the decision open without saying so. That is usually where behavior moves when you did not expect it to.
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