## Lecture Slides (Preview)

> [!NOTE]
> This release adds new capabilities for Lecture Slides, which remain
under active development and are not yet officially supported in Groups.
APIs, features, and UI/UX may change before final release.
>
> Lecture Slides mode is currently visible only to institutional admins
when creating an assistant.

### New Features
* The Lecture Slides editor now includes a slide timeline with PDF
thumbnails, slide selection, and question markers so instructors can
move through a deck and its Knowledge Checks from one timeline-style
view.
* Instructors can now add, edit, and delete Lecture Slide Knowledge
Checks directly in the slide editor.
* Lecture Slide Knowledge Checks now support three authoring modes: full
instructor-authored questions, partial drafts for the model to complete,
and marker-only questions where the instructor chooses the slide break
and lets the model write the full question.
* Instructors can now edit Knowledge Check prompts, spoken intros,
answer choices, correct-answer selection, and per-answer spoken feedback
from the assistant editor.
* Instructor-authored Knowledge Checks can now be included when creating
or updating Lecture Slide assistants, instead of relying only on
generated questions.

### Updates & Improvements
* Lecture Slide generation now preserves complete instructor-authored
questions exactly and avoids generating duplicate questions after the
same slide.
* Partial Knowledge Check drafts and marker-only question requests are
now passed into manifest generation so the model can complete or create
questions at the requested slide positions.
* Saving Knowledge Check narration or feedback edits now queues only the
affected question audio for regeneration.
* Changing the Lecture Slides voice or requesting audio regeneration now
resets both slide narration audio and Knowledge Check audio.
* The assistant save flow now treats Lecture Slide question edits as
first-class changes and includes them in the unsaved-changes summary.