Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, and non-destructive hints, but the description adds non-obvious behavior: no auth required, rate-limiting, the {error} response for missing identifiers, and the backward-compatibility reason for the me_events name. Nothing contradicts the annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.