Set parameters via REST interface

[former_member1083312]

I'm not succeeding in updating document parameters using REST API; here is what I'm using:

PUT .../raylight/v1/documents/33903/parameters/3 with payload:

{
    "parameters":{
        "parameter": {
            "id": 3,
            "answer": {
                "values": {
                    "value": [
                        "2019/9"
                    ]
                }
            }
        }
    }
}

The returned answer is instead:

{
    "parameter": {
        "@optional": "false",
        "@type": "prompt",
        ...
        "id": 3,
        ...
        "answer": {
            ...
            "info": {
                ...
                "previous": {
                    "value": [
                        "2015\/12"
                    ]
                }
            },
            "values": {
                "value": [
                    "2015\/12"
                ]
            }
        }
    }
}

How can I properly set new prompt parameters?