Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already documents slug, role and message, including the enum glosses. The description restates the role semantics ("view" to read, "edit" to change) in prose but adds no format, constraint, or syntax beyond what the schema carries; baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.