nova/doc/api_samples/os-server-groups/server-groups-list-resp.json

{
    "server_groups": [
        {
            "id": "616fb98f-46ca-475e-917e-2563e5a8cd19",
            "name": "test",
            "policies": ["anti-affinity"],
            "members": [],
            "metadata": {}
        }
    ]
}