Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover safety (readOnly, idempotent, non-destructive). The description adds meaningful context beyond that: the token acts as a credential ('treat as a password, do not share publicly') and that the response includes meeting-link sync status. This is useful behavioral disclosure the annotations don't provide.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.