curl --request POST \
  --url https://api.lightspark.com/grid/2025-10-13/sandbox/cards/{id}/simulate/return \
  --header 'Authorization: Basic <encoded-value>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "cardTransactionId": "Transaction:019542f5-b3e7-1d02-0000-000000000100",
  "amount": 1500
}
'

import LightsparkGrid from '@lightsparkdev/grid';

const client = new LightsparkGrid({
  username: process.env['GRID_CLIENT_ID'], // This is the default and can be omitted
  password: process.env['GRID_CLIENT_SECRET'], // This is the default and can be omitted
});

const response = await client.sandbox.cards.simulate.return(
  'Card:019542f5-b3e7-1d02-0000-000000000010',
  { amount: 1500, cardTransactionId: 'Transaction:019542f5-b3e7-1d02-0000-000000000100' },
);

console.log(response.issuerTransactionToken);

package com.lightspark.grid.example

import com.lightspark.grid.client.LightsparkGridClient
import com.lightspark.grid.client.okhttp.LightsparkGridOkHttpClient
import com.lightspark.grid.models.sandbox.cards.simulate.RefundRequest
import com.lightspark.grid.models.sandbox.cards.simulate.SimulateReturnParams
import com.lightspark.grid.models.sandbox.cards.simulate.SimulateReturnResponse

fun main() {
    val client: LightsparkGridClient = LightsparkGridOkHttpClient.fromEnv()

    val params: SimulateReturnParams = SimulateReturnParams.builder()
        .id("Card:019542f5-b3e7-1d02-0000-000000000010")
        .refundRequest(RefundRequest.builder()
            .amount(1500L)
            .cardTransactionId("Transaction:019542f5-b3e7-1d02-0000-000000000100")
            .build())
        .build()
    val response: SimulateReturnResponse = client.sandbox().cards().simulate().return_(params)
}

{
  "issuerTransactionToken": "f3a1c2d4-5b6e-7890-abcd-ef0123456789"
}

{
  "status": 400,
  "code": "INVALID_INPUT",
  "message": "<string>",
  "details": {
    "errors": [
      {
        "field": "identifier",
        "constraint": {
          "format": "email",
          "pattern": "^\\d{5}(-\\d{4})?$",
          "enum": [
            "SSN",
            "ITIN",
            "NON_US_TAX_ID"
          ],
          "minLength": 1,
          "maxLength": 500
        },
        "message": "Value is not one of the allowed enum members."
      }
    ]
  }
}

{
  "status": 401,
  "code": "UNAUTHORIZED",
  "message": "<string>",
  "details": {}
}

{
  "status": 403,
  "code": "FORBIDDEN",
  "message": "<string>",
  "details": {}
}

{
  "status": 404,
  "code": "TRANSACTION_NOT_FOUND",
  "message": "<string>",
  "details": {}
}

{
  "status": 409,
  "code": "TRANSACTION_NOT_PENDING_PLATFORM_APPROVAL",
  "message": "<string>",
  "details": {}
}

{
  "status": 500,
  "code": "GRID_SWITCH_ERROR",
  "message": "<string>",
  "details": {}
}