Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden. 'Fetch' implies a read operation and the description adds useful output-handling context (write to SKILL.md, call again with include_files if extra files are indicated). However, it does not state auth needs, rate limits, error behavior, or explicit read-only safety, leaving clear gaps.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.