To integrate Siri capabilities in your app, you should add an extensions as you would do while creating an iOS 10 Widget (old Today View Extension) or a custom keyboard.
1- In the project settings, select your iOS app target and go to Capabilities tab
2- Enable the Siri capability
1- Go to File -> New -> Target...
2- Select iOS -> Application Extension from the left pane
3- Double-click Intents Extension from right
According to Apple:
Intents Extension template builds an Intents extension that allows your app to handle intents issued by system services like Siri and Maps.
4- Choose a name, and be sure to check "Include UI Extension"
By doing this steps, two new targets (Intents Extension and UI Extension) are created, and by default they contain Workout Intent code. For different types of Siri requests, see Remarks.
Anytime you want to debug your extension, just select the Intent scheme from the available schemes.
You can't test SiriKit apps in the Simulator. Instead, you need a real device.