Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds nothing beyond that — no note on error behavior for unknown IDs, no indication of scope or visibility, and no distinguishing detail for an openWorldHint=true tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.