Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations and no output schema, the description carries the burden of explaining behavior. It only says 'List' which implies a read operation, but it does not disclose pagination, response shape, filtering absence, or what an 'operation' contains. This is insufficient for a tool with zero structured behavior metadata.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.