Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already establish readOnly, idempotent, openWorld and non-destructive behavior, so the safety profile is covered. The description adds genuinely useful operational context beyond that: automatic rate-limit handling, the 2000/day and 600/minute API quotas, and the 50-URL per-call ceiling. It does not describe failure behavior for oversized batches, keeping it short of a 5.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.