Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already provide readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable context by specifying the kind of data returned (status, dates, distance, partner id) and the bulk execution behavior ('Bulk support: accepts order_ids'). This goes beyond what annotations alone convey, without contradicting them.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.