Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and destructiveHint=false, and the description ('Get portfolio statistics') is consistent with those. The description adds the data categories (returns, allocation, risk) but does not disclose additional behaviors such as response formatting, pagination, or required permissions. Given the strong annotations, this is acceptable but not exceptional.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.