Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuine behavioral context beyond that: newest-first ordering, single-page granularity, a defined termination condition (empty page), and downstream usability of the match id.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.