ScribeLens

Accuracy and limits

AI detection is pattern analysis, and reading a result well is what makes it useful. This page covers what a detection score actually measures, how to interpret one, and why ScribeLens shows the sentence-level evidence behind every verdict rather than a number on its own.

What a detection score actually measures

A detector does not know who wrote your text. It measures how closely the writing resembles patterns common in AI-generated output: vocabulary choice, sentence rhythm, structural predictability, and variation across the document.

So a high score means "this text shares measurable patterns with AI-generated writing." It does not mean "an AI wrote this." Those two statements get conflated constantly, and the gap between them is where people get hurt.

Who gets falsely flagged most often

False positives are not random. They cluster in predictable groups, which is exactly why a raw score should never drive a decision on its own.

False negatives happen too

The reverse error is just as real. Lightly edited AI output, AI text run through a paraphrasing tool, or a hybrid draft where a person rewrote generated content can all read as human.

This is why a low score is not a clearance certificate any more than a high score is a conviction.

How to use detection responsibly

The practical answer is to stop treating the number as the output and start treating the evidence as the output.

Read which sentences were flagged and what patterns triggered them. Compare against the author's other work and their drafting history. Then have a conversation. A detector should narrow where you look, not decide what you conclude.

Why we say this out loud

It would be easy to advertise a confident accuracy figure. We do not, because a single number cannot describe performance across every writing style, subject, and language — and because overstated confidence is precisely what leads to students being wrongly accused.

ScribeLens is built to be audited rather than trusted blindly. That is why every verdict comes with the sentence-level evidence behind it.

Frequently asked questions

How accurate is AI detection?

Detection is probabilistic, not proof. Accuracy varies with text length, writing style, subject, and language, so no single figure describes it honestly. Use sentence-level evidence and document context before making decisions.

Can a detector prove someone used AI?

No. It can show that text shares patterns with AI-generated writing. Proof of authorship requires context such as drafting history and direct discussion with the author.

Why do ESL writers get flagged more often?

Writers working in a second language often rely on more regular sentence structures and vocabulary, which pattern-based analysis can read as formulaic. This is a known limitation of the entire category, not a judgement on the writing.

What should I do if I am wrongly flagged?

Present your process: drafts, version history, notes, and outlines. Ask that the sentence-level evidence be reviewed rather than the overall score alone.

See the evidence, not just a number

Run any text and inspect the sentence-level signals behind the verdict. Free, no signup required.