Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond annotations which mark the tool as destructive and idempotent, the description adds the nuance of two delete modes (soft and hard). This clarifies the tool's behavior beyond what the annotations alone provide, though it doesn't cover potential cascading effects or restoration options.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.