Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the transparency burden. It discloses that get returns package summaries and that full=true changes the output to full package lists, but it does not describe list's behavior, output format, or whether operations are read-only. The 'set full=true' instruction implies a parameter not present in the schema, adding subtle confusion.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.