Alexa Presentation Language で Pager を自動スライドする ref: https://qiita.com/isann_tech/items/8ef507af808dff9fa22b

file0.js

    return handlerInput.responseBuilder
      .speak('Hello APL.')
      .reprompt('Hello APL.')
      .addDirective({
          "type"       : "Alexa.Presentation.APL.RenderDocument",
          "token"      : "token",
          "document"   : {
            "type"        : "APL",
            "version"     : "1.0",
            "theme"       : "dark",
            "import"      : [],
            "resources"   : [],
            "styles"      : {},
            "layouts"     : {},
            "mainTemplate": {
              "item": [
                {
                  "type"          : "Container",
                  "alignItems"    : "center",
                  "direction"     : "column",
                  "justifyContent": "center",
                  "item"          : [
                    {
                      "type"  : "Image",
                      "source": "https://zono-img.appspot.com/480x480/00BFFF.jpg",
                      "width" : "480",
                      "height": "480"
                    }
                  ]
                }
              ]
            }
          }
        }
      )
      .getResponse();

file1.js

    return handlerInput.responseBuilder
      .speak('Hello APL.')
      .reprompt('Hello APL.')
      .addDirective(
        {
          "type"    : "Alexa.Presentation.APL.RenderDocument",
          "token"   : "token",
          "document": {
            "type"        : "APL",
            "version"     : "1.0",
            "theme"       : "dark",
            "import"      : [],
            "resources"   : [],
            "styles"      : {},
            "layouts"     : {},
            "mainTemplate": {
              "item": [
                {
                  "type"          : "Container",
                  "alignItems"    : "center",
                  "direction"     : "column",
                  "justifyContent": "center",
                  "item"          : [
                    {
                      "type"             : "Pager",
                      "width"            : "480",
                      "height"           : "480",
                      "textAlignVertical": "center",
                      "textAlign"        : "center",
                      "navigation"       : "normal",
                      "initialPage"      : 0,
                      "id"               : "foobar",
                      "item"             : [
                        {
                          "type"  : "Image",
                          "source": "https://zono-img.appspot.com/480x480/0033FF.jpg",
                          "width" : "480",
                          "height": "480"
                        },
                        {
                          "type"  : "Image",
                          "source": "https://zono-img.appspot.com/480x480/00BFFF.jpg",
                          "width" : "480",
                          "height": "480"
                        },
                        {
                          "type"  : "Image",
                          "source": "https://zono-img.appspot.com/480x480/FFBFFF.jpg",
                          "width" : "480",
                          "height": "480"
                        }
                      ]
                    }
                  ]
                }
              ]
            }
          }
        }
      )
      .addDirective(
        {
          "type"    : "Alexa.Presentation.APL.ExecuteCommands",
          "token"   : "token",
          "commands": [
            {
              "type"       : "AutoPage",
              "componentId": "foobar",
              "duration"   : 3000
            }
          ]
        }
      )
      .getResponse();