Make a Siri custom intent generally available

[Alan Warren]

Hello

I'd like to develop a Siri custom intent that will allow the user to trigger a call by voice to Siri that causes an HTTPS end point to be called that returns a textual response for Siri to speak. I've done some research and can see how to achieve this. However, I cannot find any information on how to subsequently make the custom intent available to other Apple device users. Is there a publication mechanism similar to that for custom Alexa skills?

It's been suggested to me that I would need to create an iOS or watchOS app and make it available from the App Store. Is this the only and/or best way of achieving my objective?

Thanks