Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The annotations already establish read-only, idempotent, non-destructive behavior. The description adds value by specifying the type of network operation (fetching from a URL) and what information will be returned (fields, geometry type, record count, capabilities), providing behavioral expectations beyond the annotations. No contradictions with annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.