Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the behavioral disclosure burden. 'List' implies a non-destructive read operation, which is helpful, but it does not disclose output format, ordering, or any other behavioral details. For a zero-parameter read tool this is acceptable, though not rich.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.