Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already provide readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds useful behavioral context by noting it covers both sales and purchases and reports payment, escrow/settlement, and fulfillment status, but it does not address return shape, pagination, or ordering behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.