Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is fully covered. The description adds genuine context beyond that — rows carry an IRS source URL and a checked date, and the response includes the dataset page URL and license — but is silent on truncation behavior when limit is hit or on what happens with unknown filter keys.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.