Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds meaningful behavioral context: geographic restriction to Spain, public surface only, ranked results, and alias resolution behavior documented in _meta.sector_resolved_from. No contradictions.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.