Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=true), and the description adds substantial context beyond them: the post is retained in the workspace, re-calling is a no-op, non-draft posts are rejected, and CMS preview drafts may be deleted as a side effect. Minor tension worth noting: it discloses a genuine deletion ('deletes that preview draft') while destructiveHint=false, though that applies to the primary resource, so it does not rise to a contradiction.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.