Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds one real fact beyond that — the data is fake/synthetic, so results should not be treated as authoritative — but says nothing about pagination behavior, result ordering, or total count, which matters for a paged browse endpoint.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.