curl --request POST \
  --url https://sandbox.tight.com/v6/invoicing/itemTemplates \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "data": [
    {
      "name": "Standard Service Fee",
      "id": "tili_28868401",
      "status": "ACTIVE",
      "description": "Standard hourly service fee",
      "amount": 5000,
      "quantity": "1.0",
      "price": "50.0",
      "salesTax": {
        "value": "8.875",
        "type": "PERCENT"
      },
      "glAccountId": "gla_28868401",
      "customData": {
        "internal_key": "some_internal_key",
        "some_other_field": 23434
      }
    }
  ]
}
'

{
  "data": [
    {
      "data": {
        "id": "tili_28868401",
        "name": "Standard Service Fee",
        "status": "ACTIVE",
        "description": "Standard hourly service fee",
        "amount": 5000,
        "quantity": "1.0",
        "price": "50.0",
        "salesTax": {
          "value": "8.875",
          "type": "PERCENT"
        },
        "glAccount": {},
        "customData": {
          "internal_key": "some_internal_key",
          "some_other_field": 23434
        }
      },
      "error": [
        {
          "message": "<string>",
          "param": "<string>"
        }
      ]
    }
  ],
  "error": [
    {
      "message": "<string>",
      "param": "<string>"
    }
  ]
}