Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries full burden for behavioral disclosure. It indicates a destructive action ('delete'), but doesn't mention permissions required, whether the action is reversible, what happens if the invitation is already accepted/expired, or what the response looks like. For a destructive tool with zero annotation coverage, this is insufficient.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.