Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond readOnlyHint=true, the description discloses real behavioral detail: keys are returned by prefix, the public key value is included because it is not secret, and secret keys are never returned or stored. It also warns that new public tables become role-accessible so RLS must be on, which is meaningful side-effect context the annotations do not cover.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.