Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The tool has zero parameters, so schema coverage is effectively 100% and there are no parameter semantics to explain. The description adds value by providing the actual tier definitions and rates, which helps the agent understand what the output will contain, meeting the baseline for a parameterless tool.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.