How does SiriKit parse commands for Pinterest

Question

Could anyone enlighten me how does Siri recognise this sentence for Pinterest?

Pinterest: Find specific ideas you've saved: "Hey Siri, find women's fashion Pins on Pinterest." https://www.imore.com/siri-apps-faq

I suspect its using INSearchForPhotosIntentHandling since the sentence has the closest reference to photos. The second thing I suspect is the use of Custom Vocabulary by swapping out "photo" with "Pins".

https://developer.apple.com/documentation/sirikit/registering_custom_vocabulary_with_sirikit

These are my current speculations for now, but I would like some clarity on this.

Use Case

I have an app that is centered around food reviews and I am hoping to integrate Siri to assist in Searching for food.

An example command:
"Hey Siri, find Japanese food in MY_APP."
"Hey Siri, find Japanese food reviews in MY_APP."

My keywords could be Food or Food Reviews or Reviews.

Answer 1

Siri process the request for your app based on the Intent that is supported by the app. There are only limited categories that is supported by Siri now. So the siri know the vocabulary for these categories and it also uses your apps custom vocabulary to process the user given string to call the corresponding Intent from your extension.

IMO, you can consider reviews as notes and support INSearchForNotebookItemsIntentHandling by modifying the siri vocabulary.

Or the best way is to write to apple to add your corresponding domain in the siri's list of domains