Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, openWorld, idempotent, and non-destructive behavior. The description adds meaningful operational context beyond annotations: it identifies the upstream sources (Google/Cloudflare DoH), the HTTP method, and the cost per call, which helps an agent understand external dependencies and side effects.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.