For rehearsing or delivering a presentation, pitch, talk, keynote, lecture, webinar, demo or thesis defense from the presenter's own slides, including a deck made earlier in the conversation. Creates a talk the presenter can rehearse out loud and present, from a PDF, PPTX or PPT deck, optionally with a per-slide speaker script and grounding documents for the private Q&A. The deck comes from exactly one of: deck_upload_id (a file uploaded through aitho_prepare_upload; its bytes go straight to Aitho and never pass through the conversation; no hosting required), deck_file (the file inline as base64, capped at 256,000 characters, about 190 KB), or deck_url (a deck already on the web, including gamma.app links, which are exported to PDF server-side). Returns a talk_id and status immediately; deck parsing and document extraction run asynchronously and are reported by aitho_get_ingest_status. clips[slide].narrate_over sets whether the presenter speaks over a video on that slide (true: the teleprompter keeps tracking) or the video carries the narration (false, the default: the teleprompter pauses). Requires Presenter Pro; a free account can create one talk this way.