curl --request GET \
  --url https://api.metronome.com/v1/billable-metrics \
  --header 'Authorization: Bearer <token>'

{
  "data": [
    {
      "name": "data transfer (GB)",
      "id": "9570e4f3-d1da-4b95-ba81-bd40ee002727",
      "aggregation_type": "SUM",
      "aggregation_key": "bytes",
      "event_type_filter": {
        "in_values": [
          "cpu_usage"
        ]
      },
      "property_filters": [
        {
          "name": "cpu_hours",
          "exists": true
        },
        {
          "name": "region",
          "exists": true,
          "in_values": [
            "EU",
            "NA"
          ]
        },
        {
          "name": "machine_type",
          "exists": true,
          "in_values": [
            "slow",
            "fast"
          ]
        }
      ],
      "group_keys": [
        [
          "region"
        ],
        [
          "machine_type"
        ]
      ],
      "custom_fields": {
        "envionment": "production"
      }
    }
  ],
  "next_page": null
}