Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The readOnlyHint annotation already signals that this is a safe read operation, so the description does not need to repeat that. The description adds the scoping detail "by its numeric ID," which is useful but not a behavioral trait. It does not disclose return format, possible errors, or authentication needs, but for a simple getter with a read-only annotation, this is acceptable.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.