The `/sandbox/item/fire_webhook` endpoint is used to test that code correctly handles webhooks. This endpoint can trigger the following webhooks: `DEFAULT_UPDATE`: Webhook to be fired for a given Sandbox Item simulating a default update event for the respective product as specified with the `webhook_type` in the request body. Valid Sandbox `DEFAULT_UPDATE` webhook types include: `AUTH`, `IDENTITY`, `TRANSACTIONS`, `INVESTMENTS_TRANSACTIONS`, `LIABILITIES`, `HOLDINGS`. If the Item does not support the product, a `SANDBOX_PRODUCT_NOT_ENABLED` error will result. `NEW_ACCOUNTS_AVAILABLE`: Fired to indicate that a new account is available on the Item and you can launch update mode to request access to it. `SMS_MICRODEPOSITS_VERIFICATION`: Fired when a given same day micro-deposit item is verified via SMS verification. `LOGIN_REPAIRED`: Fired when an Item recovers from the `ITEM_LOGIN_REQUIRED` without the user going through update mode in your app. `PENDING_DISCONNECT`: Fired when an Item will stop working in the near future (e.g. due to a planned bank migration) and must be sent through update mode to continue working. `RECURRING_TRANSACTIONS_UPDATE`: Recurring Transactions webhook to be fired for a given Sandbox Item. If the Item does not support Recurring Transactions, a `SANDBOX_PRODUCT_NOT_ENABLED` error will result. `SYNC_UPDATES_AVAILABLE`: Transactions webhook to be fired for a given Sandbox Item. If the Item does not support Transactions, a `SANDBOX_PRODUCT_NOT_ENABLED` error will result. `PRODUCT_READY`: Assets webhook to be fired when a given asset report has been successfully generated. If the Item does not support Assets, a `SANDBOX_PRODUCT_NOT_ENABLED` error will result. `ERROR`: Assets webhook to be fired when asset report generation has failed. If the Item does not support Assets, a `SANDBOX_PRODUCT_NOT_ENABLED` error will result. `USER_PERMISSION_REVOKED`: Indicates an end user has revoked the permission that they previously granted to access an Item. May not always fire upon revocation, as some institutions’ consent portals do not trigger this webhook. Upon receiving this webhook, it is recommended to delete any stored data from Plaid associated with the account or Item. `USER_ACCOUNT_REVOKED`: Fired when an end user has revoked access to their account on the Data Provider's portal. This webhook is currently sent only for PNC Items, but may be sent in the future for other financial institutions. Upon receiving this webhook, it is recommended to delete any stored data from Plaid associated with the account or Item. Note that this endpoint is provided for developer ease-of-use and is not required for testing webhooks; webhooks will also fire in Sandbox under the same conditions that they would in Production (except for webhooks of type `TRANSFER`).