Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The annotations already declare the tool as read-only, idempotent, and non-destructive, so the safety profile is covered. The description adds value beyond that by disclosing that results are limited to stable id, title, and citable URL, and that complete content requires a separate fetch call. This gives the agent an accurate model of the tool's partial-result behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.