I guess that this example should be helpful when debugging slave's environments

core/src/main/resources/hudson/model/Computer/_script.jelly

@@ -29,6 +29,7 @@ THE SOFTWARE.
 <j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form">
   <t:scriptConsole>
     <pre>println System.getenv("PATH")</pre>
+    <pre>println "uname -a".execute().text</pre>
     <p>
       ${%This execution happens in the slave agent JVM.}
     </p>