Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and closed-world scope. The description adds the one thing annotations cannot convey: the response is 'clean markdown', which matters since no output schema exists. It omits error behavior for nonexistent paths, which keeps it short of a 5.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.