Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations provide comprehensive safety information (readOnlyHint: true, destructiveHint: false, idempotentHint: true, openWorldHint: true), so the agent knows this is a safe, repeatable read operation. The description adds minimal value beyond annotations - the '(GET)' notation reinforces read-only nature but doesn't describe return format, authentication requirements, or rate limits. No contradiction with annotations exists.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.