Per
https://developer.smartthings.com/docs/automations/getting-started-with-automations, looks like rules created outside of the API aren't visible/available in the API:
View attachment 10522
In general, Rules ("automatic routines") are designed to be triggered by events (time of day, sensor activation, etc.), vs. manually, so maybe that's why this isn't straightforward. If you want to avoid cluttering up your list of scenes with scenes that only exist to trigger a rule, the only thing I can think of would be to
- set up virtual switches (one per rule, and accessible from the "Labs" icon in the app on the "Menu" tab)
- trigger each rule based on its associated switch being turned on
- turn off the switch at the end of the rule
- hide the virtual switches in the app's Device display using its "Select Devices to Use" option (in its three-dot menu). Alternatively you could just create a Room called "Virtual Switches" or "Rule Switches" or something and put all the virtual switches there...