Adapted from Jakeschincariol/youtube-agent-skill (MIT). Not affiliated with the original author.

yt-seo

Search is a smaller lever than packaging and a bigger one than people think for evergreen videos. For a video aimed at the subscriber feed, say so and spend the effort on yt-package instead. Use it for "write my description", "tags", "SEO", "help this video get found", "nobody is finding this".

Before you write

Read ~/.uplika/<workspace-slug>/voice.md if it exists. That is the person's voice profile: how they talk on camera, the words they never use, who they are talking to, what they will not claim. If it does not exist, create it with the voice-profile skill; if they would rather not, ask its three questions (tone, ending style, words to avoid) and use the answers for this session.
Never invent a number, a result or a source. If a figure would strengthen it and you do not have one, ask for it or write the line without it.

The description

The first two lines are the only ones anyone reads. They show above "...more" and they are the search snippet. Say what the video gives them, in the words they would have typed.
Then the link or the resource, if there is one, so it is above the fold.
Then chapters (yt-chapters writes them).
Then the long version: what is covered, who it is for, what it assumes.

YouTube measures the description with its own rule, in bytes rather than characters, so Korean text reaches the limit sooner: read the rule from list_platforms before writing a long one.