Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description adds the payload composition, which helps an agent decide whether a fetch is worth it, but it says nothing about missing/invalid IDs, external Wikipedia dependency timing, or freshness of listener stats.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.