responseSchema

val responseSchema: Schema? = null

The Schema object allows the definition of input and output data types. These types can be objects, but also primitives and arrays. Represents a select subset of an OpenAPI 3.0 schema object. If set, a compatible response_mime_type must also be set. Compatible mimetypes: application/json: Schema for JSON response.

If response_schema doesn't process your schema correctly, try using response_json_schema instead.