Skills are not just documentation. They include computability (programs/scripts), data (assets), and the documentation (resources) to use everything effectively.

Programs and data are the basis of deterministic results that are accessible to the llm.

Embedding an sqlite database with interesting information (bus schedules, dietary info, or a thousand other things) and a python program run by the skill can access it.

For Claude at least, it does it in a VM and can be used from your phone.

Sure, skills are more convention than a standard right now. Skills lack versioning, distribution, updates, unique naming, selective network access. But they are incredibly useful and accessible.