Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond annotations (non-destructive, idempotent), the description discloses the important post-condition that the workflow returns in a disabled state and the ordering prerequisite for a deleted sheet. These are non-obvious behaviors an agent would otherwise get wrong.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.