Variables in Monitoring Templates

This is the only documentation I've ever found on variables.

https://www.solarwinds.com/documentation/en/flarehelp/orionplatform/content/core-orion-variables-and-examples-sw1115.htm

A quick way to figure out variables beyond that though is by going into Settings -> All Settings -> Manage Alerts -> Action Manager, then edit an WriteToNPMEventLog action and click Insert Variable. Note that variables are relative to the entity being referenced. SolarWinds will take that into account if you use it to add them, however if you manually type in the variables or copy from one alert action to another it may not always work.

Best of luck!

If you're referencing an alert on an application, here's the variables that you would need for the nodes caption, and applications name, respectively.

Node Caption: ${N=SwisEntity;M=Node.Caption}
Application Name: ${N=SwisEntity;M=ApplicationAlert.ApplicationName}