curl --request GET \
  --url https://api-sandbox.endl.io/api/v0/accounts/cus_9FpQ2LmZ8sW4TxKn1BvD \
  --header 'API-KEY: <api-key>' \
  --header 'Api-Version: 2026-09.1'

{
  "data": [
    {
      "id": "acct_8f2a1c4e9b7d43a6",
      "name": "USD Account",
      "displayName": "Operating USD",
      "status": "ACTIVE",
      "category": "ONRAMP",
      "currency": "USD",
      "balance": { "amount": "12450.00", "currency": "USD" },
      "createdAt": "2026-09-02T11:41:07Z",
      "updatedAt": "2026-09-18T08:12:55Z"
    },
    {
      "id": "acct_7e3f95b2c08a416d",
      "name": "AED Account",
      "displayName": "Dirham balance",
      "status": "ACTIVE",
      "category": "FIAT",
      "currency": "AED",
      "balance": { "amount": "9437.57", "currency": "AED" },
      "createdAt": "2026-08-21T06:55:02Z",
      "updatedAt": "2026-09-19T12:30:41Z"
    }
  ],
  "balances": {
    "ONRAMP": {
      "holdings": [ { "amount": "12450.00", "currency": "USD" } ]
    },
    "FIAT": {
      "holdings": [ { "amount": "9437.57", "currency": "AED" } ],
      "total": { "amount": "9437.57", "currency": "AED" }
    }
  }
}

{
  "code": 400,
  "message": "User id is required",
  "status": "ERROR",
  "data": null,
  "errors": [
    {
      "code": "ERRACC_1000",
      "message": "User id is required",
      "field": "userId"
    }
  ]
}

{
  "code": 401,
  "message": "Partner API key required",
  "status": "ERROR",
  "data": null,
  "errors": [
    {
      "code": "ERRCORE_1004",
      "message": "Partner API key required",
      "field": null
    }
  ]
}

{
  "code": 403,
  "message": "Insufficient permissions",
  "status": "ERROR",
  "data": null,
  "errors": [
    {
      "code": "ERRCORE_1005",
      "message": "Insufficient permissions",
      "field": null
    }
  ]
}

{
  "code": 404,
  "message": "User with ID 'cus_…' not found",
  "status": "ERROR",
  "data": null,
  "errors": [
    {
      "code": "ERRREF_1001",
      "message": "User with ID 'cus_…' not found",
      "field": "userId"
    }
  ]
}

{
  "code": 405,
  "message": "HTTP … is not supported for this endpoint",
  "status": "ERROR",
  "data": null,
  "errors": [
    {
      "code": "ERRCORE_1001",
      "message": "HTTP … is not supported for this endpoint",
      "field": null
    }
  ]
}

{
  "code": 429,
  "message": "Rate limit exceeded, please retry later",
  "status": "ERROR",
  "data": null,
  "errors": [
    {
      "code": "ERRCORE_1006",
      "message": "Rate limit exceeded, please retry later",
      "field": null
    }
  ]
}

{
  "code": 500,
  "message": "An error occurred while processing your request",
  "status": "ERROR",
  "data": null,
  "errors": [
    {
      "code": "ERRCORE_1000",
      "message": "An error occurred while processing your request",
      "field": null
    }
  ]
}