Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so all parameters are already explained (gruppe, dienstherr, tarifvertrag, employmentType, period_key). The description reinforces the either/or relationship between dienstherr and tarifvertrag with 'oder', but adds no new syntactic or format details. Given the high schema coverage, a baseline of 3 is appropriate; the description does not need to compensate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.