Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare it a non-read-only, non-destructive, open-world operation. The description adds context annotations can't: it is an approval action a headless caller must supply, requires the write scope, and produces drafts rather than live deliverables. Only the failure/edge behavior (e.g., no pending plan) is unstated.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.