public function api($name)
    {
        $this->initializeClient($this->url, $this->client);

        $class = 'Rs\\VersionEye\\Api\\' . ucfirst($name);

        if (class_exists($class)) {
            return new $class($this->client);
        } else {
            throw new \InvalidArgumentException('unknown api "' . $name . '" requested');
        }
    }