curl --request GET \
  --url https://api.egp.scale.com/v5/evaluation-groups/{group_id}/schema \
  --header 'x-api-key: <api-key>'

{
  "evaluation_group_id": "<string>",
  "evaluation_schemas": [
    {
      "evaluation_id": "<string>",
      "total_items": 1,
      "fields": [
        {
          "field_name": "<string>",
          "data_type": "<string>",
          "item_count": 1,
          "source": "data",
          "object": "field_schema"
        }
      ],
      "object": "evaluation_schema",
      "is_sampled": false,
      "sample_size": 1
    }
  ],
  "object": "evaluation_group_schema"
}