Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the transparency burden. It discloses the ABS Census 2021 source, the 2011/2016/2021 census points, and calls the projection tail 'modelled,' which is a useful caveat. It does not explicitly state that the call is read-only or describe error behavior, but the wording clearly implies a data lookup and the data composition is transparent.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.