Skill Title
One short paragraph: who invokes this, what situation they're in, and what outcome they want. Write it so the model understands the intent, not just the task.
Rules
A few strong constraints beat many weak ones. Bold the first sentence of each rule, then explain it in one or two more.
The most important constraint goes first. Usually: what the skill must NOT do (scope it), or what must always lead the output (order it).
A second rule. For example: tone, honesty requirements, what to do when information is missing.
Output
Exactly what the response should look like — format, length cap, required sections, and what to omit. The more concrete this section is, the more consistent the results. Example shape:
Section one — what goes here, how long.
Section two — what goes here. Omit entirely when it doesn't apply (say so).
End with the single behavior that keeps the skill sharp, e.g. "Commit to one recommendation; never offer a menu."