Marketing Cloud API
jCustomer Key
Customer keys allow you to identify and search for an asset by a data value known only by you. A customer key is a unique value across your enterprise that is typically stored in your database. The customer key is not a required field, and if you don't provide a value, a unique GUID will be created for you.
Add a customer key to the asset as a string with a 36-character limit, using the customerKey attribute.
Sample Asset with Customer Key
{
"name": "NTO Welcome Series Email",
"assetType": {
"id": 207,
"name": "templatebasedemail"
},
"customerKey": "090c69e7-59ac-4286-8733-f8f7613ab470"
}