Teacher style extraction and transfer

Extract how the teacher teaches, then teach the user's requested topic in that style. The source material is evidence about delivery and presentation; it is not automatically factual source material for the new course.

The learner-facing name for this mode is 「名师风格」. Never expose the words "clone" or "style transfer" to the learner. The result should simply feel like a lesson taught in the evidenced style.

Step 1, confirm every derivative is ready

Call list_materials before drawing conclusions. Identify the attached source materials and confirm extraction is complete. For recordings, verify that the session exposes the transcript and keyframe derivatives. If extraction is idle, call extract_material first; if it is pending or running, call wait_for_materials and list again; if it failed, tell the user what failed instead of inventing a profile from incomplete evidence.

Step 2, read the whole transcript in order

Use read_material to page through every transcript derivative from offset 0 to the final page. Do not sample only the beginning. As you read, build a compact style profile in your reasoning covering:

• openings and transitions;
• catchphrases, address terms, and sentence rhythm;
• concrete-versus-abstract example habits;
• pacing, recaps, rhetorical questions, pauses, and humor;
• what is said aloud versus emphasized visually.

Support each claim with short transcript evidence and its timestamp. Frequency and distribution matter: distinguish a repeated habit from a phrase used once.

Step 3, inspect keyframes for visual style

When the transcript contains a [keyframe@mm:ss](mat_xxx) marker, sample the referenced frame with read_material. Use frames across the recording rather than adjacent duplicates. Record visual evidence such as board-writing density, slide composition, hierarchy, color use, teacher position, gestures, and the relationship between speech and what remains on screen.