Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so all four parameters (matrix, n_splits, max_combinations, seed) are already documented in the schema. The description only restates the matrix orientation ('periods by variants') and adds nothing about seed, n_splits, or max_combinations, so baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.