Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate mutation and idempotency, but the description adds useful behavioral detail: goal_md must be non-empty, tenant scoping can cause a 404, and the call returns a predictable object with updated_at and next_step. This exceeds what the annotations alone provide.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.