Transcribe a YouTube video and save it as a Markdown file built for an LLM to read: front matter with the video's facts, a linked chapter index, and the text in paragraphs with timestamps. By default it does NOT return the transcript, only the file path and a summary (title, channel, duration, word count and section list), so you can then read the whole file or just the section you need. Uses the video's own language unless another one is requested.

Show which captions a YouTube video has (manual and automatic), its own language, its duration and how many chapters it carries. Useful before transcribing when you are unsure the language you want exists.