Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds the useful context that the information is 'current' and includes concurrent operations and data sizes, but it does not describe the output shape or any refresh/accuracy behavior. With annotations carrying the main burden, this is acceptable but not rich.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.