Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, non-destructive, and openWorldHint=false. The description adds substantive context beyond that: the catalog is 'bounded' (matching openWorldHint=false), it does not execute paid outcomes, and it does not mutate user data. It stops short of describing result payload behavior, but the output schema covers that.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.