curl --request PUT \
  --url 'https://api.hubapi.com/integrators/timeline/v3/{appId}/event-templates/{eventTemplateId}?hapikey=' \
  --header 'Content-Type: application/json' \
  --data '
{
  "id": "1001298",
  "name": "PetSpot Registration",
  "headerTemplate": "Registered for [{{petName}}](https://my.petspot.com/pets/{{petName}})",
  "detailTemplate": "Registration occurred at {{#formatDate timestamp}}{{/formatDate}}\n\n#### Questions\n{{#each extraData.questions}}\n  **{{question}}**: {{answer}}\n{{/each}}\n\nEDIT",
  "tokens": [
    {
      "name": "petName",
      "label": "Pet Name",
      "type": "string",
      "objectPropertyName": "firstname"
    },
    {
      "name": "petAge",
      "label": "Pet Age",
      "type": "number"
    },
    {
      "name": "petColor",
      "label": "Pet Color",
      "type": "enumeration",
      "options": [
        {
          "value": "white",
          "label": "White"
        },
        {
          "value": "black",
          "label": "Black"
        },
        {
          "value": "brown",
          "label": "Brown"
        },
        {
          "value": "yellow",
          "label": "Yellow"
        },
        {
          "value": "other",
          "label": "Other"
        }
      ]
    }
  ]
}
'

{
  "id": "1001298",
  "objectType": "contacts",
  "createdAt": "2020-02-12T20:58:26Z",
  "updatedAt": "2020-02-12T20:58:26Z",
  "name": "PetSpot Registration",
  "headerTemplate": "Registered for [{{petName}}](https://my.petspot.com/pets/{{petName}})",
  "detailTemplate": "Registration occurred at {{#formatDate timestamp}}{{/formatDate}}\n\n#### Questions\n{{#each extraData.questions}}\n  **{{question}}**: {{answer}}\n{{/each}}\n\nEDIT",
  "tokens": [
    {
      "name": "petAge",
      "type": "number",
      "createdAt": "2020-02-12T20:58:26Z",
      "updatedAt": "2020-02-12T20:58:26Z",
      "label": "Pet Age",
      "options": []
    },
    {
      "name": "petColor",
      "type": "enumeration",
      "createdAt": "2020-02-12T20:58:26Z",
      "updatedAt": "2020-02-12T20:58:26Z",
      "label": "Pet Color",
      "options": [
        {
          "value": "white",
          "label": "White"
        },
        {
          "value": "black",
          "label": "Black"
        },
        {
          "value": "brown",
          "label": "Brown"
        },
        {
          "value": "yellow",
          "label": "Yellow"
        },
        {
          "value": "other",
          "label": "Other"
        }
      ]
    },
    {
      "name": "petName",
      "type": "string",
      "createdAt": "2020-02-12T20:58:26Z",
      "updatedAt": "2020-02-12T20:58:26Z",
      "label": "Pet Name",
      "objectPropertyName": "firstname",
      "options": []
    }
  ]
}