Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the behavioral disclosure burden. It does add useful behavior: matching is case-insensitive and operates on substring input against installed SDK enums. However, it does not disclose the return format, whether values are also returned with names, or any edge-case behaviors such as empty results.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.