curl --request POST \
  --url https://v1.api.flux-os.com/contracts \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --header 'x-user-id: <api-key>' \
  --data '
{
  "external_id": "<string>",
  "term": "<unknown>",
  "transaction_type": "<unknown>",
  "type": "<unknown>",
  "start_date": "2023-12-25",
  "volume": 123,
  "volume_measurement_unit": "<unknown>",
  "measurement_type": "<unknown>",
  "pricing_basis": "<unknown>",
  "settlement_currency": "<unknown>",
  "payment_term": "<unknown>",
  "end_date": "2023-12-25",
  "differential_unit_amount": null,
  "differential_currency": null,
  "differential_measurement_unit": null,
  "percentage_of_index": null,
  "percentage_of_index_measurement_unit": null,
  "percentage_of_benchmark": null,
  "percentage_of_benchmark_measurement_unit": null,
  "eq": null,
  "index": null,
  "product_category": null,
  "stream": null,
  "benchmark": null,
  "stream_wadf": null,
  "feeder_wadf": null,
  "broker_transaction_id": null
}
'

{}