Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so safety is covered. The description goes beyond them by disclosing the return shape (Markdown plus structuredContent matching the outputSchema), server-side caching, and the backing service (Perseids Morpheus). It does not mention rate limits, failure modes for unknown forms, or ambiguity handling.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.