Correct fulfillmentMessages format for DialogFlow Google Assistant

Question

I'm trying to use the Java DialogFlow API to build a webhook response for Google Assistant. My responses work fine in DialogFlow's 'Try It Now' feature, but Google Assistant keeps saying "isn't responding right now. Try again later".

As an experiment, I managed to get Google Assistant working by using a non-webhook response (i.e. through the normal DialogFlow Intent UI). When I looked in my History, I see the working response looked like this:

"queryText": "GOOGLE_ASSISTANT_WELCOME",
  "action": "input.welcome",
  "fulfillmentMessages": [
    {
      "text": {
    "text": [
      "[{\"type\":\"simple_response\",\"platform\":\"google\",\"textToSpeech\":\"Hello\"}]"
    ]
      }
    }

This seems very strange to me, as the text body is actually a further JSON encoded object (containing textToSpeech amongst other fields). When I use the Java DialogFlow API like this:

List<String> texts = new ArrayList<>();
texts.add( "Foo" );
message.setText( new GoogleCloudDialogflowV2IntentMessageText().setText( texts ));

I get a different format:

  "fulfillmentMessages": [
    {
      "text": {
    "text": [ "Foo" ]
      }
    }

That Google Assistant says:

MalformedResponse: Failed to parse Dialogflow response into AppResponse because of empty speech response"

Even if I try forcing an encoded JSON string as my text body, it still doesn't seem to work.

What is the correct way to return a default message format so that Google Assistant can read it? I tried simpleResponse and that didn't work either

sgodsell sgodsell · Accepted Answer · 2019-05-15T15:55:25

The following is a minimum response needed to hear a response

{
  "payload": {
    "google": {
      "expectUserResponse": true,
      "richResponse": {
        "items": [
          {
            "simpleResponse": {
              "textToSpeech": "Welcome! Do you want me to change color or pause spinning? You can also tell me to ask you later."
            }
          }
        ]
      }
    }
  }
}

Naturally with java you can use the API's to generate the needed output responses. Plus if you use basicCards or Images for smart displays, then it definitely helps a lot more to use the API's instead. You can also check the response from the simulator.

Correct fulfillmentMessages format for DialogFlow Google Assistant

1 Answers