Hannes Unfortunately not. custom Shortcuts, outside of the default Siri supported functionality, currently do not support input. iOS 13 will add some limited functionality for this, but we are not allowed to support that until iOS 13 is released.
Things uses the built-in INNotesIntent Siri functionality. Built-in Siri functionality can be supported by apps and can have inputs. Those built-in commands need support in the Shortcuts app to show up tho. All the notes commands are supported in Shortcuts, but for the Payments command, only Send Payment/Request are supported by Shortcuts.
Please keep in mind there's a difference between Shortcuts and Siri functionality:
- Siri functionality is fully interactive in Siri and when supported by Apple's Shortcuts app, support input parameters
- "Siri Shortcuts" on the other hand are just pre-set commands that 3rd party apps tell the system are possible: they don't support custom inputs.
Built-in functionality such as Making payments / request / transfering money / viewing balances / adding notes / viewing notes are Siri functionality and thus supports custom inputs. Other custom Siri Shortcuts don't support inputs. Not all Siri functionality is supported by the Shortcuts app unfortunately.