> ## Documentation Index > Fetch the complete documentation index at: https://docs.gr4vy.com/llms.txt > Use this file to discover all available pages before exploring further. # Gift card simulator The gift card simulator is a sandbox-only connector that can be used to simulate responses for balance checks, gift card redemptions and refunds, and [issuing](/reference/gift-cards/issue-gift-card) and [activating](/reference/gift-cards/activate-gift-card) gift cards. The values for the `error_code`, `balance` and `expiration_date` can be simulated by passing in different pin and gift card numbers. This can be used when testing your integration. ## Credentials To configure the connection, you need to set the following credentials. | Credential | Description | | ---------- | -------------------------------------------------- | | API Key | This is not validated and can be set to any string | ## Error codes The `pin` field is used to simulate error codes: * Starts with `0`: Reserved for successful responses. Example: `01000`. * Starts with `1`: Validation error returned by the provider, `error_code` populated as explained below. Example `10001`. * Starts with `2`: Server error, `error_code` populated as explained below. Example: `20010`. * Starts with `3`: Client error, `error_code` populated as explained below. Example: `30003`. The rest of digits of the `pin` number are used to determine the `error_code`: | `error_code` | Description | PIN last digits | | :------------------------------ | :-------------------------------------------------------- | :-------------- | | `invalid_gift_card` | Gift card details are invalid, for example number or pin. | `0000` | | `expired_card` | Gift card expired. | `0001` | | `inactive_card` | Gift card is inactive. | `0002` | | `invalid_service_credentials` | Service credentials are not valid. | `0003` | | `invalid_amount` | Amount is invalid. | `0004` | | `incorrect_currency` | Currency was rejected by service. | `0005` | | `insufficient_funds` | Amount exceeds available balance. | `0006` | | `invalid_service_configuration` | Service is incorrectly configured. | `0007` | | `operation_canceled` | Operation was canceled as part of the batch. | `0008` | | `service_error` | Internal server error or upstream processing error. | `0009` | | `service_network_error` | Service was unreachable or experienced a timeout. | `0010` | | `unknown_error` | Mapping to a more specific error code failed. | `0011` | | `max_gift_cards_reached` | Buyer reached the maximum number of stored gift cards. | `0012` | | `suspected_fraud` | Service flagged the transaction as suspected fraud. | `0013` | | `canceled_payment_method` | Gift card reported lost, stolen, or otherwise canceled. | `0014` | | `duplicate_transaction` | Transaction is a duplicate of a previous transaction. | `0015` | | `unexpected_state` | Service or account is in an unexpected state. | `0016` | Any other value is mapped to `unknown_error` too. ## Refunds Similar logic is applied to trigger error cases for refunds, but the last digit of the refund amount is used, rather than the PIN. * Ends with `0`: Reserved for successful responses. Example: `1000`. * Ends with `1`: Validation error returned by the provider. Example `1001`. * Ends with `2`: Server error. Example: `1002`. * Ends with `3`: Client error. Example: `1003`. ## Balance For endpoints returning the gift card balance, its value is the `pin` number as an integer. The recommendation is that it starts with `0`, so it's always considered a successful response. For example, a PIN of `01234` results in a gift card balance of `12.34`. ## Activation [Activating](/reference/gift-cards/activate-gift-card) a gift card uses the `pin` to simulate errors, and the `error_code` is taken from the remaining digits as described in the error codes section. The prefixes differ slightly from a balance check. * Omit the `pin`: successful activation. * Starts with `1`: Client error. Example: `10001`. * Starts with `2`: Server error. Example: `20010`. * Starts with `3`: Client error. Example: `30003`. * Starts with `4`: Validation error returned by the provider. Example: `40006`. On a successful activation, the resulting balance is the `amount` you send. Omit the amount and the balance is derived from the `pin` exactly as described in the [Balance](#balance) section. ## Issuance [Issuing](/reference/gift-cards/issue-gift-card) a virtual gift card has no `pin` or `number` to simulate errors with, so the `amount` is used instead. The last digit selects the type of error and the remaining digits determine the `error_code`. * Ends with `0`: Reserved for successful responses. Example: `5000`. * Ends with `1`: Client error. Example: `10001`. * Ends with `2`: Server error. Example: `10002`. * Ends with `3`: Client error. Example: `10003`. * Ends with `4`: Validation error returned by the provider. Example: `10004`. ## Expiration date For endpoints returning the expiration date, the gift card `number` is considered. * A gift card number that starts with `0` results in an expiration date in the past. For example: `0000444455556666` results in an expiration date set in the past. Currently, this is set to a month in the past, but this behavior may change. * A gift card number that starts with `1` results in an expiration date in the future. For example: `1000444455556666` results in an expiration date set in the future. Currently, this is set to a month in the future, but this behavior may change. * Otherwise, any other gift card has no expiration date. For example: `9000444455556666` results in a gift card without an expiration date.