Carl's note-taking interface, where he keeps the extra-long War Crime description and its private addendum.
Carl had the extra-long description of War Crime saved in his scratch pad. Reading it there, he noticed The AI's unusual enthusiasm, which immediately set off his alarm bells, and the more he considered the spell's direct and implied consequences the more he was overwhelmed with horror — especially at what casting it at full potential might do to Donut.
The scratch pad also holds the closing section about the Operatic Collective warlord, the identity reset, and the Warlord Hortense Leadership Unit — a passage Carl believes did not appear for anyone other than himself as far as he could tell, and which gave him a terrible, foreboding feeling about the spell.
The tool through which Carl studies the War Crime description and spots the AI's private aside.