buttons

{
  "messages": [
    {
      "attachment": {
        "type": "template",
        "payload": {
          "template_type": "button",
          "text": "Hello!",
          "buttons": [
            {
              "type": "show_block",
              "block_name": "name of block",
              "title": "Show Block"
            },
            {
              "type": "web_url",
              "url": "https://rockets.chatfuel.com",
              "title": "Visit Website"
            },
            {
              "url": "https://rockets.chatfuel.com/api/postback",
              "type":"json_plugin_url",
              "title":"Postback"
            }
          ]
        }
      }
    }
  ]
}