Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint=true and readOnlyHint=false, so the mutation profile is covered. The description adds one genuinely useful fact beyond that — that the associated sign-in is destroyed too — but says nothing about permissions required, reversibility, or confirmation behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.