Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint=true, idempotentHint=true and openWorldHint=true, so the safety profile is covered externally. The description adds nothing beyond that — it does not say what deletion entails (e.g. whether the vector index entry and embeddings are removed, whether the underlying session/document record survives, or whether authorization is required).
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.