const files = await client.files.retrieve([{id: 123}, {externalId: 'abc'}]);

{
  "items": [
    {
      "name": "<string>",
      "id": 4503599627370496,
      "uploaded": true,
      "createdTime": 1730204346000,
      "lastUpdatedTime": 1730204346000,
      "externalId": "my.known.id",
      "directory": "<string>",
      "source": "<string>",
      "mimeType": "image/jpeg",
      "metadata": {},
      "assetIds": [
        4503599627370496
      ],
      "dataSetId": 4503599627370496,
      "sourceCreatedTime": 1730204346000,
      "sourceModifiedTime": 1730204346000,
      "securityCategories": [
        4503599627370496
      ],
      "labels": [
        {
          "externalId": "my.known.id"
        }
      ],
      "geoLocation": {
        "type": "Feature",
        "geometry": {
          "type": "Point",
          "coordinates": [
            123
          ]
        },
        "properties": {}
      },
      "uploadedTime": 1730204346000,
      "instanceId": {
        "space": "<string>",
        "externalId": "<string>"
      }
    }
  ]
}