Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the baseline is 3. The description adds minimal extra semantics: it lists the filter parameters and mentions pagination, but the schema already documents each parameter in detail. The description's added value is the 'newest-first' ordering and the sample-tier note, which are not parameter-specific. Thus, 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.