Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the agent knows this is a closed-world, non-destructive write. The description adds the useful fact that it does not alter published revisions, but it does not say what record is created, whether it is idempotent, or what side effects occur, so added value is modest.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.