Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The annotations already establish readOnly and idempotent behavior, so the description does not need to restate safety. It adds useful behavioral context by specifying the results are 'live', the alternatives are 'same-category', and `target` must not be a catalog listing slug.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.