Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description must carry the load, and it does: it documents every body field plus semantics the schema omits, e.g. maxParticipants null = unlimited, timezone must be an IANA name, date format YYYY-MM-DD, and which fields accept null to clear.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.