Next hop address is not mandatory in VPP CLI, e.g.

ip route add 192.0.2.11/32 via loop0 out-labels 3

JSPO equivalent that needs to be supported

{
  "static-lsp": [
    {
      "name": "192.0.2.11",
      "config": {
        "in-segment": {
          "ip-prefix": "192.0.2.11/32"
        },
        "operation": "impose-and-forward",
        "outgoing-label": 3,
        "outgoing-interface": "loop0"
      }
    }
  ]
}