Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds useful behavior beyond that: the fixed page size of 24 and the exact card fields returned, which tells the agent what a result set contains. No rate limits or pagination-end behavior mentioned.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.