On a fresh install of Statamic 3.4 and Peak Studio starter kit, I got this error.

 Disk [assets] does not have a configured driver.

  at vendor/laravel/framework/src/Illuminate/Filesystem/FilesystemManager.php:137
    133▕     {
    134▕         $config ??= $this->getConfig($name);
    135▕
    136▕         if (empty($config['driver'])) {
  ➜ 137▕             throw new InvalidArgumentException("Disk [{$name}] does not have a configured driver.");
    138▕         }
    139▕
    140▕         $name = $config['driver'];
    141▕

All I had to do was go to config/filesystems.php and add this new block under disks

'assets' => [
            'driver' => 'local',
            'root' => public_path('assets'),
            'url' => '/assets',
            'visibility' => 'public',
        ],