Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already establish read-only, idempotent, non-destructive behavior. The description goes well beyond this by disclosing concrete limits (max 366 days, 1000 requests), explicit failure rather than partial totals, and the accounting distinction that daily completed amounts are separated by network and asset, not settlement-date revenue. These are valuable behavioral traits not present in the annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.