Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, and destructiveHint=false, so the mutation and open-world nature is captured structurally. The description adds nothing further — no note on required permissions, what the created account can do, or whether default_sharing_groups grants access.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.