Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare read-only and non-destructive behavior, so the description carries a lower burden for safety. It adds important behavioral context: the synthesis is built from live web sources, includes a signed provenance receipt, and costs $1.00 USDC per call. It does not disclose return format, latency, or rate limits, but for a read-only call the added details are meaningful.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.