Webhook - Instant Trigger - Parsed Items

I’m adding a webhook to an App Make, no problem to define and register the endpoint. I have defined a module (Instant Trigger) so that the interface can retrieve “Parsed Items” from the body of a POST request. I’d like to do the same thing when retrieving parameters from a GET request, i.e: Parsing Items form Url query parameters, like a standard Webhook. How do I set up the Communication zone to achieve this? Is this possible?