Laravel5.2 Auth::attempt 自定义登录验证报错

FatalThrowableError in EloquentUserProvider.php line 114:
Type error: Argument 1 passed to Illuminate\Auth\EloquentUserProvider::validateCredentials() must be an instance of Illuminate\Contracts\Auth\Authenticatable, instance of App\Models\Worker given, called in E:\papp\dream\vendor\laravel\framework\src\Illuminate\Auth\SessionGuard.php on line 385