Kohana includes several tools to help you debug your application.
// Display a dump of the $foo and $bar variables echo Debug::vars($foo, $bar);
Kohana also provides a method to show the source code of a particular file using [Debug::source].
// Display this line of source code echo Debug::source(__FILE__, __LINE__);
If you want to display information about your application files without exposing the installation directory, you can use [Debug::path]:
// Displays "APPPATH/cache" rather than the real path echo Debug::path(APPPATH.'cache');
If you are having trouble getting something to work correctly, you could check your Kohana logs and your webserver logs, as well as using a debugging tool like Xdebug.