Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It states the destructive action ('Delete') but lacks critical details: whether deletion is permanent or reversible, permission requirements, error conditions (e.g., invalid contact_id), or what happens on success (e.g., no return value vs confirmation). This is inadequate for a mutation tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.