code: @Nonnull
      public String getDescription() {
          Stapler stapler = Stapler.getCurrent();
          if (stapler != null) {
              try {
                  WebApp webapp = WebApp.getCurrent();
                  MetaClass meta = webapp.getMetaClass(this);
                  Script s = meta.loadTearOff(JellyClassTearOff.class).findScript("newInstanceDetail");
                  if (s == null) {
                      return "";
                  }
                  DefaultScriptInvoker dsi = new DefaultScriptInvoker();
                  StringWriter sw = new StringWriter();
                  XMLOutput xml = dsi.createXMLOutput(sw, true);
                  dsi.invokeScript(Stapler.getCurrentRequest(), Stapler.getCurrentResponse(), s, this, xml);
                  return sw.toString();
              } catch (Exception e) {
                  LOGGER.log(Level.WARNING, null, e);
                  return "";
              }
          } else {
              return "";
          }
      }
docs: A description of this kind of item type. This description can contain HTML code but it is recommended that
  you use plain text in order to be consistent with the rest of Jenkins.
  
  This method should be called from a thread where Stapler is handling an HTTP request, otherwise it will
  return an empty string.
  
  @return A string, by default the value from newInstanceDetail view is taken.
  
  @since 2.0