Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The annotations already establish read-only, idempotent, non-destructive, closed-world behavior, so the description does not need to repeat those. It adds meaningful behavioral context by clarifying that identifiers are opaque and that names, emails, secrets, and another user's account are not returned, which is exactly the kind of privacy and scope boundary an agent needs before calling a profile tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.