Config PTOOLS_IP

I tried to install webtools but i have access only to controller tab. For the rest, i cannot. I think it's from the PTOOLS_IP config? I received the following msg:

Phalcon\Db\Exception: The descriptor must be an array
#0 /var/www/phalcon-devtools/scripts/Phalcon/Web/Tools.php(313): Phalcon\Db\Adapter\Pdo->__construct(NULL)
#1 [internal function]: Phalcon\Web\{closure}()
#2 [internal function]: Phalcon\DI\Service->resolve(NULL, Object(Phalcon\DI\FactoryDefault))
#3 /var/www/phalcon-devtools/scripts/Phalcon/Web/Tools.php(181): Phalcon\DI->getShared('db')
#4 /var/www/phalcon-devtools/scripts/Phalcon/Web/Tools/controllers/ControllerBase.php(61): Phalcon\Web\Tools::getConnection()
#5 /var/www/phalcon-devtools/scripts/Phalcon/Web/Tools/controllers/ModelsController.php(30): ControllerBase->listTables(true)
#6 [internal function]: ModelsController->indexAction()
#7 [internal function]: Phalcon\Dispatcher->dispatch()
#8 /var/www/phalcon-devtools/scripts/Phalcon/Web/Tools.php(322): Phalcon\Mvc\Application->handle()
#9 /var/www/phalcon_test/public/webtools.php(26): Phalcon\Web\Tools::main('/var/www/phalco...', '192.168.')
#10 {main}**