What does "Support shorthand-syntax, json-file and yaml-file" in the az cli documentation mean?

[Tom Wolverson (TWolversonReply)]

https://learn.microsoft.com/en-us/cli/azure/logic/workflow?view=azure-cli-latest#az-logic-workflow-update-optional-parameters

--definition
The definition. Support shorthand-syntax, json-file and yaml-file. Try "??" to show more.

What does this mean? As far as I'm aware, the only workflow definition syntax for Logic Apps is JSON. Are there other syntaxen supported but not documented?

[Tom Wolverson (TWolversonReply)]

Further to that, what does "Try "??" to show more." mean?