Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds meaningful context those annotations cannot: results are owner-scoped (the caller only) and only webhook presence is exposed, which implies no secret leakage.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.