Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden, and it does disclose the read-only return contents (numeric-flag columns, row count, provenance banner), which is the main behavioral trait for this tool. However it says nothing about output format, whether a row limit applies, or error behavior on an unavailable dataset.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.