Simulate a card authorization reversal

Simulate a merchant cancelling a card authorization before it settles — a hotel releasing a hold, or a store voiding a purchase that never went through. Use it to see how your integration handles an authorization that disappears without ever clearing. Send amount to reverse only part of the authorization, or leave it out to reverse all of it. The transaction must still be fully open: once any part of it has settled, it can no longer be reversed. Grid processes the reversal in the background. A full reversal sets status: VOIDED and sends a CARD_TRANSACTION.VOIDED webhook. A partial reversal leaves the transaction AUTHORIZED with a smaller hold.

Production returns 404 on this path.

POST /sandbox/cards/{id}/simulate/authorization_reversal

cURL

fullReversal

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

202

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

Authorizations

Authorization · string · header · required

API token authentication using format <api token id>:<api client secret>

Path Parameters

id · string · required

The id of the card the reversal applies to.

Body

application/json

Request body for POST /sandbox/cards/{id}/simulate/authorization_reversal: which authorization to reverse, and optionally how much of it.

cardTransactionId · string · required

The authorization to reverse. It must still be fully open, with nothing settled against it yet.

Example:

"Transaction:019542f5-b3e7-1d02-0000-000000000100"

amount · integer<int64>

How much to reverse, in the smallest unit of the transaction's currency (cents for USD). Leave it out to reverse the whole authorization. Send an amount to reverse only that much and leave the rest on hold.

Example:

1250

Response

202

application/json

Simulation accepted. The resulting card operation is delivered asynchronously via the issuer's events webhook. Returns the issuer transaction token that correlates the simulated event.

Response body for the sandbox card-event simulators. The simulate call pokes the card issuer's sandbox; the resulting card operation is delivered asynchronously via the issuer's events webhook, never synchronously in this response.

issuerTransactionToken · string · required

The card issuer's transaction token for the simulated event. Correlates the eventual webhook-delivered card operation back to this simulate call.

Example:

"f3a1c2d4-5b6e-7890-abcd-ef0123456789"