The RoonCommandLine command roon -l playlist may work for your needs @Eric_Gross
Unfortunately, the recent update broke api calls as Roon Labs changed the Roon Core port range and many of us were assuming port 9100. Roon Labs points out that was a bad assumption on our part but they kinda yanked the rug out from under our feet with no warning. Anyway, I will have this fixed in a new release asap.
@GregD see Roon Api on Build 880: Connection refused error :(