Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the annotations (readOnlyHint, openWorldHint, destructiveHint), the description adds valuable context: data is derived from live Evlek sale and long-term-rent listings, and holiday-home inventory is explicitly excluded. This clarifies the tool's data coverage and currentness.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.