The copy desk for machine prose
Your draft is a rich tapestry of insights. pile of tells.
Every model leaves fingerprints: inflated verbs, throat-clearing openers, em dashes pacing every sentence the same way. Paste your text. We mark each one in red, say what it gives away, and write it out.
Source
written out for you flagged only, needs your call
Waiting for text
Rewrite
Your rewrite lands here.
Not rewritten yet
What the pen found
The marking list
Eight kinds of fingerprint.
Red Pen carries — patterns. Each one is here because models reach for it far more often than people do.
One straight answer about detectors.
Red Pen does not promise to beat Turnitin, GPTZero, or anything else, and you should be wary of any tool that puts a percentage on that. Detectors change weekly, they disagree with each other, and they flag plenty of human writing.
The Robot index is our own measurement, not a detector's. It scores tell density, sentence-length variance, em dash rate, opener repetition, and three-item list frequency. The same formula runs on your source and your rewrite, so the difference between the two numbers is real even though the numbers are ours.
What Red Pen actually does is make prose read better: shorter, plainer, less padded, with a rhythm that moves. That tends to help with detectors. It definitely helps with readers. Read the rewrite before you use it — it is a fast editor, not a careful one.