unified authentication for RTC for apps using both REST and CLI

My team is developing various tools, apps, what-have-you that combine REST API and RTC scm commands to automate various tasks and extend RTC functionality on the client side.

For CLI commands, users save their credentials using the scm login command, prior to using any of these tools. We currently have to get the user's credentials by other, less secure, and/or less robust means for REST service calls.

Is there some way to leverage the credentials stored by scm login and use them when making REST service calls?

Any other suggestions?