Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, and the schema already explains invite_code, actions, action_number, label, icon, sound, and requires_ack in detail. The description adds no parameter-level detail beyond what the schema provides, so the baseline of 3 is appropriate; the schema carries the parameter-semantics burden.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.