Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so safety is covered. The description goes beyond that by disclosing the terminal status values (pending/indexed/failed/revoked) and, more valuably, the deprecation window for the legacy alias vespa_chunk_count — real lifecycle context an agent could not infer from annotations alone.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.