curl --request POST \
  --url https://api.galileo.ai/v2/projects/{project_id}/experiments/available_columns \
  --header 'Galileo-API-Key: <api-key>'

{
  "columns": [
    {
      "id": "<string>",
      "label": "<string>",
      "description": "<string>",
      "group_label": "<string>",
      "multi_valued": false,
      "allowed_values": [
        "<unknown>"
      ],
      "sortable": true,
      "filterable": true,
      "is_empty": false,
      "applicable_types": [],
      "is_optional": false,
      "roll_up_method": "<string>",
      "metric_key_alias": "<string>"
    }
  ]
}