Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden; it discloses the API key or payment requirement, states that data is read from onchain registration, and explains the freshness semantics of the sweep (re-probing every minute, rolling registry basis). The word 'read' implies a non-mutating operation, though it never explicitly states read-only or covers error/rate-limit behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.