Let’s walk through the Lambda function for an example Popular Language skill.

The index.js file to the right contains a Lambda function with empty handlers for the initial speaking portions of this skill.

We’ll add Alexa responses for two scenarios:

• When the user launches the skill (triggers LaunchRequest)
• When a user responds to the question from Alexa (triggers LanguageIntent)

Set up Alexa Response

Alexa’s response is generated using the Alexa SDK’s this.response.speak() method.

this.response contains functions used to set up a response from Alexa, like this:

this.response.speak("Hello, welcome to Codecademy!")

Send Alexa Response

Once the response is set up, we use this.emit(':responseReady') to send our response to the user’s Alexa device.

'LaunchRequest': function () {
    this.response.speak("Hello, welcome to Codecademy!");
    this.emit(':responseReady');
  },

Together, these two lines (.speak() and .emit(':responseReady')) set up and send the response to the user’s Alexa device. One thing to note, is that .speak() generates a response and then instructs Alexa to close the session.

When creating a conversation, you usually don’t want to close the session. Alexa SDK’s .listen() method allows us to instruct the device to keep the session open to allow a conversational dialogue.