External (Merchant) Id

When a new merchant is able to process payments for a given payment type, the merchant_activated_for_payment_type webhook will fire. This event provides your software notification that you can enable the merchant in your system for payment processing as well.

The easiest way to identify the merchant in your webhook code is to utilize the external_id field, which is returned in the body. This field is populated with the value you submit along with the application. In the application api, the field is called external_id and in the online version of the application externalid=MY_ID can be appended to the query string.

See Webhooks Overview for more.