Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema only describes the opacity parameter (0-255), leaving frame and layer with no schema descriptions. The description adds the conceptual meaning that a cel is a layer+frame combination, which helps interpret frame and layer. However, it does not clarify whether these are optional (since only opacity is required), what they default to, or whether they expect names or indices.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.