Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With robust annotations (readOnlyHint, idempotentHint, etc.), the description adds only the phrase 'read-only' which is redundant. It does not disclose additional behavioral traits beyond what annotations already provide, such as rate limits or side effects.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.