Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are supplied, so the description carries the burden; 'Read this' implies a non-destructive read and it discloses the returned fields, which is genuinely useful. It says nothing about whether the values are static, how often they change, or any access constraints — acceptable but not rich for a zero-parameter metadata call.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.