This tool hides AI writing by rewriting the plot, not the word choice.
An open-source tool called sepia passed 1,473 GitHub stars five days after its release. It builds on a study of 61,608 stories where narrative structure alone flagged AI fiction. That measure scored 93.2, so sepia repairs plot and pacing before it touches word choice.
Why it mattersDetectors that read structure will not be fooled by a pass through a thesaurus. That cuts both ways, for teachers checking work and for writers leaning on AI.
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