file/app/Documents/PolicyDocument.php

<?php

namespace App\Documents;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Jenssegers\Mongodb\Eloquent\Model;

class PolicyDocument extends Model
{
    use HasFactory, BaseDocument;

    protected $connection = 'mongodb';

    protected $fillable = [
        'name',
        'labels',
        'needs',
    ];
    protected $casts = [
      'needs' => 'array'
    ];

}