Query form fields of a task


I’d like to query all form fields of a specific task. I used the endpoint GET /task/id/form-variables. Unfortunately, this has a drawback. This endpoint yields all serializable process variables. I want an endpoint, that is restricted to the form fields, that are requested in the modeler. The endpoint GET /task/id/rendered-form yields only those form fields, however in HTML instead of JSON. What I would like to have is exactly this information, but in JSON. Is there an endpoint for this, or a workaround at least?