Specifically, I'm looking to create a standalone web page that will make a REST call to PAM. PAM would then instantiate an existing process (based on a parameter from the REST call), and return data gathered by the process to the caller as JSON (or CSV, etc.).
I have cross-referenced the Community board (here), and the CA Process Automation Web Services API Reference, and the built-in 'View Tutorials' in PAM before posting this question.
Unfortunately, I have only found examples for REST (and SOAP) web service calls from within PAM. I have not been able to find an example of external calls into PAM.