Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnlyHint=false, destructiveHint=false, and idempotentHint=true. The description adds meaningful behavioral context by stating that other contacts on the account are demoted, which is a side effect beyond simple assignment. This is valuable transparency, though it does not detail all potential effects or preconditions.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.