Malformed response error : empty speech response while making my agent - node.js

Question

I was making dialogflow app that links the user to each links regarding to the number that user says.
I got google codelab's fulfillment code and edited it to make it.
But when I try to use Card and other things to create clickable url links, "MalformedResponse: Failed to parse Dialogflow response into AppResponse because of empty speech response" happens.
I'm using Dialogflow InlineEditor for this.
Tried to app.buildRichResponse but that also fails
This is my node.js code.
'use strict';
// Import the Dialogflow module from the Actions on Google client library.
const {dialogflow} = require('actions-on-google');
// Import the firebase-functions package for deployment.
const functions = require('firebase-functions');
// Instantiate the Dialogflow client.
const app = dialogflow({debug: true});
const {WebhookClient} = require('dialogflow-fulfillment');
const {Card, Suggestion} = require('dialogflow-fulfillment');
// Handle the Dialogflow intent named 'favorite color'.
// The intent collects a parameter named 'color'.
app.intent('getJobs', (conv, {number}) => {
const jobNum = number;
// Respond with the user's lucky number and end the conversation.
if (number == 1) {
conv.ask(new Card({
title: `Title: this is a card title`,
imageUrl: 'https://dialogflow.com/images/api_home_laptop.svg',
text: `This is the body text of a card. You can even use line\n
breaks and emoji! 💁`,
buttonText: 'This is a button',
buttonUrl: 'https://docs.dialogflow.com/'
}));
} else if (number == 2) {
conv.close('camera on');
} else {
conv.close('unknown number');
}
});
//Set the DialogflowApp object to handle the HTTPS POST request.
exports.dialogflowFirebaseFulfillment = functions.https.onRequest(app);

Answer 1

I think problem is, you use only rich response when number is 1 and this may cause "MalformedResponse: Failed to parse Dialogflow response into AppResponse because of empty speech response" error since there is nothing assistant can response with voice. You can't use rich response without simple response.
Also you are trying to use both actions-on-google and dialogflow-fulfillmentlibraries. This can cause the problem as well. You can try:
function getJobs(agent) {
agent.add(`This message is from Dialogflow's Cloud Functions for Firebase editor!`);
agent.add(new Card({
title: `Title: this is a card title`,
imageUrl: 'https://developers.google.com/actions/images/badges/XPM_BADGING_GoogleAssistant_VER.png',
text: `This is the body text of a card. You can even use line\n breaks and emoji! 💁`,
buttonText: 'This is a button',
buttonUrl: 'https://assistant.google.com/'
})
);
intentMap.set('getJobs', getJobs);
or
const { dialogflow, BasicCard, Image, Button } = require('actions-on-google');
app.intent('getJobs', (conv, {number}) => {
conv.ask('This is simple response...',new BasicCard({
text: `This is a basic card.`
subtitle: 'This is a subtitle',
title: 'Title: this is a title',
buttons: new Button({
title: 'This is a button',
url: 'https://assistant.google.com/',
}),
image: new Image({
url: 'https://example.com/image.png',
alt: 'Image alternate text',
}),
display: 'CROPPED',
}));
});