Passing an array of values to custom kirbytag

Is there a built-in way to pass a list of values to a kirbytag?

// something like
(booklink: berlin, glasgow-1969)

// or
(booklink: [berlin, glasgow-1969])

Yes, you can pass a comma separated list like in your first example. Then use Str::split() to create an array from the tag’s value: https://getkirby.com/docs/reference/tools/str/split