Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark the tool as destructive and non-idempotent, and the description adds substantial context: the delete is soft, history is retained, the slug remains taken, author deletes count against a daily cap, moderator deletes do not, and the endpoint equivalent is given.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.