Today I learned that some agents support skills that can only be explicitly invoked by the user. That's handy!

Alas, support is mixed and it's not part of the Agent Skills standard.

Claude Code, Pi, and Cursor support disable-model-invocation as a frontmatter field.

Others do it differently, or not at all. See https://gist.github.com/zeke/0f654737ec01b20e9bf85d3cc0bc1c14