How can you open a URI from the command line?

I recently started playing with the app called 'Automate'. The starting block for each Automate flow provides a URI. Can this URI be used to initiate a flow? Can I accomplish this from the command line? Specifically, I would like to call Automate flows from within a Termux environment. I assume this can be done with am start ... but I haven't had any luck trying different commands (and I have successfully used am from within Termux before, so I don't think that's an issue). I have very limited knowledge of Android intents. I tried running am start -d content://rest-of-uri and I received a prompt asking which app to open, I chose Automate and the notification appeared for a second but the flow didn't run.