Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are present, so the description carries the full burden. It states 'List all subdomains' but does not clarify the scope (e.g., across all domains), whether the operation is read-only, or any output details. The word 'List' implies a read operation, but additional behavioral traits are not disclosed.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.