A few things to note when creating triggers and adding your own merge tags. All triggers come with four default merge tags that shops can use in messages after your trigger is fired based on the data we have for a shop and subscriber. They are:

First Name: label: "First Name", value: "{first_name}"
Last Name: label: "Last Name", value: "{last_name}"
Shop Name: label: "Shop Name", value: "{shop_name}"
Shop Link: label: "Shop Link", value: "{shop_link}"

You can of course add more tags if you'd like to the above but do note that these tags will be available to a shop that is using your custom trigger.

One other thing to note about trigger merge tags. We do not currently support the use of camel case in variable naming of merge tags. Therefore, if you try to pass a variable name like "{fullName}", it will be converted to "{fullname}" instead. We do, however, support both kebab and snake casing of variable names (for example "{full-name}" and "{full_name}" will not be changed).