Closing the Fragment: Sappho 31 and the Composition Layer as a Surface of Classical Reception is an article by Lee Sharks in Machine-Mediated Reception Studies, deposited as version 7 on 7 November 2026, after its sixth version was declined by Classical Receptions Journal the same day, and rebuilt in place as version 8 that night. It studies one event: on 18 January 2026 Google's AI Overview, asked about Rebekah Cranes's translation of Sappho fragment 31, displayed one source, her book on Medium, and returned under her name a fifteen-line poem ending "But I must dare all.", with the gloss that the κῆνος of the first line is "you, the future reader". The source's text of the poem leaves τόλματον without an agent and marks its edge with an ellipsis, under a heading that sets κῆνος equal to the future reader. The article reads the answer as a conclusion composed within the environment those documents built: the source's reading of the seat joined to a first-person close that no document in the environment makes, and the conjunction published as the translator's, without a mark. Its wording corresponds to earlier English versions, H. T. Wharton's literal version of 1885 above all, and the article holds the correspondences as antecedents of wording, establishing no route of composition. It sets the act in the poem's transmission history, read from seated texts and first printings ('Longinus', Catullus 51, the editors Bergk and Edmonds, and the English translators from John Hall's Longinus of 1652 through a teaching gallery of thirteen versions), and reads it under two readings of the edge: as a break, and as the poem's form, with the seat at κῆνος and the agent of τόλματον held open. Closure is defined as three observable operations (added continuation, terminal selection, resolution of suspended syntax) and signature at three levels (page, edition, network). It separates three questions, the antecedents of the wording, the transformation performed and the selection of the configuration, follows two fixed queries from June to October 2026, and states a protocol for frequency, variation and causal sensitivity. Its appendices answer the two referee reports, record the later reviews, and give the line alignment. Rebekah Cranes is a heteronym of the author.