Description of the feature

From the spec:

To define a range of response codes, you may use the following range definitions: 1XX, 2XX, 3XX, 4XX, and 5XX. If a response range is defined using an explicit code, the explicit code definition takes precedence over the range definition for that code. Each response status requires a description. For example, you can describe the conditions for error responses. Markdown (CommonMark) can be used for rich text representation.

responses:
  "200":
    description: OK
  "400":
    description: Bad request. User ID must be an integer and larger than 0.
  "401":
    description: Authorization information is missing or invalid.
  "404":
    description: A user with the specified ID was not found.
  "5XX":
    description: Unexpected error.

Code example (if possible)

#[derive(ApiResponse)]
pub enum ApiError {
    #[oai(status = 400)]
    BadUserId,
    #[oai(status = 5XX)]
    UnexpectedError(#[status] http::StatusCode),
}