Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint/idempotent/destructiveHint, so the safety profile is covered, and the description is consistent with them (no contradiction). It adds that the response includes Markdown text, but says nothing about missing-document behavior or errors.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.