Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false. The description adds meaningful behavioral detail by specifying distinct output scenarios (authenticated:true vs. connect_url), which helps the agent understand the tool's conditional behavior beyond the annotation safety profile.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.