The spec needs at least name and description. Keep name short, stable and usable as a folder. Description says what it does, which task should trigger it, and what it does not cover. Do not write “handle any document”.
If you declare allowed tools, compatible hosts or a license, use values someone can check. A host may preload metadata only; hidden instructions in the body stay invisible until install.
Open SKILL.md before you install and read the frontmatter plus any scripts it names. See writing a SKILL.md and reading a skill detail page on this site. If the description and the body disagree, fix the description first.
When one repo holds several skills, their triggers must split. If both say “help you write better code”, the model picks at random or loads both.