Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
With 0% schema description coverage, the description must compensate. It clarifies that the mbid parameter is an alternative to the artist+album pair, and provides examples in the schema. This adds meaning beyond the bare schema, though individual parameter details could be richer.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.