const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    type: '/v1/regions/us-texas-1/zones/us1-a/instance-types/g1-xlarge',
    id: 'instance-d4e5f6',
    displayName: '<string>',
    description: '<string>',
    labels: {},
    instanceMetadata: [{key: '<string>', value: '<string>'}],
    hostname: '<string>',
    disks: [
      {
        sizeGb: 123,
        interface: 'SCSI',
        source: '/v1/regions/us-texas-1/compute/images/ubuntu-24.04-20260202-3',
        boot: true,
        type: 'PERSISTENT',
        mode: 'READ_ONLY'
      }
    ],
    nics: [
      {
        network: '/v1/regions/us-texas-1/projects/project-x9y8z7/compute/networks/network-g7h8i9',
        subnet: '<string>',
        ipv4Address: '<string>',
        ipv6Address: '<string>',
        vlan: 123
      }
    ],
    gpus: [{type: '<string>', count: 123}]
  })
};

fetch('https://api.k0rdent.ai/v1/regions/{region}/projects/{project}/compute/instances', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

{
  "selfLink": "/v1/regions/us-texas-1/projects/project-x9y8z7/compute/instances/instance-d4e5f6",
  "uid": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "id": "instance-d4e5f6",
  "displayName": "<string>",
  "description": "<string>",
  "labels": {},
  "type": "/v1/regions/us-texas-1/zones/us1-a/instance-types/g1-xlarge",
  "instanceMetadata": [
    {
      "key": "ssh-keys",
      "value": "admin:ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIJeaD1heScpzmiypsUSb0T3lkmg2d/onGkPviaZ2Rtgc admin@hostname\nguest:ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIBYgtXDI3X7eELjQ+D+qbJGqgfa+OqvY7jo/EuLv1ECd guest@hostname\n"
    }
  ],
  "hostname": "<string>",
  "lifecycle": {
    "status": "PROVISIONING",
    "statusMessage": "<string>"
  },
  "disks": [
    {
      "sizeGb": 123,
      "interface": "SCSI",
      "source": "/v1/regions/us-texas-1/compute/images/ubuntu-24.04-20260202-3",
      "boot": true,
      "type": "PERSISTENT",
      "mode": "READ_ONLY"
    }
  ],
  "nics": [
    {
      "network": "/v1/regions/us-texas-1/projects/project-x9y8z7/compute/networks/network-g7h8i9",
      "subnet": "<string>",
      "ipv4Address": "<string>",
      "ipv6Address": "<string>",
      "vlan": 123
    }
  ],
  "gpus": [
    {
      "type": "<string>",
      "count": 123
    }
  ],
  "createdAt": "2023-11-07T05:31:56Z",
  "updatedAt": "2023-11-07T05:31:56Z"
}