Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare this is a non-read-only, open-world mutation, but the description adds nothing beyond that: it doesn't say whose access is being granted, whether the operation is reversible or how to un-share, what permissions/organization membership are required, or what happens to existing shares. With zero annotation coverage of those semantics, the description carries the burden and fails to.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.