Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, so the safety profile is covered; the description adds useful non-annotation context (cost, no API key required, which chain the anchor lives on, and the mainnet caveat). One mild tension: openWorldHint=false while the description says it 'checks the anchor on chain (Base)', which implies an external network lookup — worth noting though not a hard contradiction for a read-only vendor-infrastructure verification. It does not describe what a failure verdict looks like.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.