Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly states the tool requires a HUD User API token and 'returns registration guidance if token is not configured', which is a valuable behavioral trait. It also explains the county_fips default behavior (statewide data when omitted). However, it does not cover error handling, rate limits, or response details, warranting a 4 rather than a 5.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.