Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden. It discloses key behaviors: async (needs follow-up), read-only (no writes), and restricted to SELECT/CTE. However, it omits how to monitor or cancel queries, and does not mention authentication or rate limits.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.