Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false), so the bar is lower; the description still adds a concrete rate limit ('no more than once an hour') and notes it 'says what to do next' and returns the address once the house exists. Auth requirements and failure behavior for an invalid ticket are not disclosed, keeping it from 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.