Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description nonetheless adds real operational context: it works without an API key on the free tier, returns a verdict block for graded lanes, and refuses an unknown slug with an error naming it. Return-format detail is somewhat redundant with the output schema.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.