How can I get the result ID from CLI test call

I’d like to get the result Id at run-time after kicking off a test call.

Perhaps I could save the result json to a file, and retrieve it there?

Can’t you script it to inspect the xml output for the test ? That’s what I do for my API usage for WPT, GTMetrix and Google PageSpeed Insights https://github.com/centminmod/google-insights-api-tools

the test id would be in the result xml file tags