Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the readOnlyHint and destructiveHint annotations, the description discloses that sign-in is required, that the result is rendered as a status card with a progress stepper and sometimes a map, and that the tool should be called again to refresh live data. These are meaningful operational details not present in the annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.