YouTube clip

Two passes: chapter the video from its transcript, then cut. Two modes decide who picks the chapters:

Strip fluff (default): pick the chapters yourself — keep teaching, demo and plausibly-demo no speech chapters, cut promo/ad and fluff — and run both passes without stopping. Report the chapter table and what was kept and cut alongside the finished clip.
Manual selection (when the user asks to choose, or the keep/cut call is genuinely unclear): present the chapter table with a recommended selection, stop, and cut only what they pick. Never download the full video before their selection.

Pass 1: chapter

Fetch metadata and captions into the scratchpad, no video download:
```
yt-dlp --skip-download --write-auto-subs --sub-lang en --convert-subs srt -o "<VIDEO_ID>.%(ext)s" "<URL>"
yt-dlp --dump-json "<URL>" | jq '{title, channel, duration_string, upload_date, chapters}'
```
Prefer creator chapters from metadata as a starting skeleton when present. If no captions exist, download audio only and transcribe with the transcribe-audio skill (Parakeet), as in youtube-transcribe.
Read the whole SRT and segment it into chapters at topic shifts. Auto-caption quirks: cues overlap and repeat as rolling lines (trust start times, not text boundaries), and timestamps can drift a second or two from the actual speech.