With iOS 12 iPhone and iPad users got the ability to create a whole slew of actions that they can trigger with a word, but all of these actions are also available to flic.
You do this by giving the flic app (on your iPhone or iPad) the instruction of:
New Action/Phone Control/Safari (open a website)
and then giving the URL
shortcuts://run-shortcut?name=Your%20shortcut%20name
if you want to pass a parameter then add &input=[input]
e.g.
shortcuts://run-shortcut?name=Quick%20Action
The first time that this is run the app asks if it’s OK to open Shortcuts but after that it’s just click and go!

Very old post but relevant to others. The way to launch an app is to open the url of the app that you want, with a 'deep link' if that app supports it. So to open Waze you want to select: New Action/Phone Control/Safari (open a website)
with the URL of https://waze.com/ul?
You can find details of how to send a parameter to waze here https://developers.google.com/waze/deeplinks/

As with so many technical requests your question isn't really clear enough as to what the problem is. It looks like you're using Postman to generate the code and wanting to post a multipart form. I can only point you to
https://ec.haxx.se/http-multipart.html .
You have my sympathies, curl is not the easiest to understand and API documentation rarely makes it easy to understand exactly what's necessary.

@samsonxander You write your scripts as you were doing under Hax but turn them into plugins. That's what I've done to create a flic that controls which internet radio station my mac plays. Hope that helps.

@Joacim
For anyone that wants their iphone to make a telephone call with flic on iOS the way to do it is this.
Set the Action to be Safari / Open a website with the URL of
tel://yourphonenumberhere
e.g.
tel://08008443456
Hope that helps you!
@mattjohns

Sorry my mistake. This only works for flic tasks from the activation center. Using a real flic still asks for dial confirmation. My error.