Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The readOnlyHint annotation already covers safety. The description adds that the result includes body and headers, which is useful behavioral context. However, it does not disclose pagination, error behavior, or any rate limits, so the added transparency is minimal.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.