The source for the example you referred to goes like this:
$(document).ready(function() {
$("#demo-input-local-custom-formatters").tokenInput(
[{
"first_name": "Arthur",
"last_name": "Godfrey",
"email": "arthur_godfrey@nccu.edu",
"url": "https://si0.twimg.com/sticky/default_profile_images/default_profile_2_normal.png"
},
{
"first_name": "Adam",
"last_name": "Johnson",
"email": "wravo@yahoo.com",
"url": "https://si0.twimg.com/sticky/default_profile_images/default_profile_2_normal.png"
},
...
],
{
propertyToSearch: "first_name",
resultsFormatter: function(item){ ... },
tokenFormatter: function(item) { ... }
});
});
tokenInput
seems to take an array of objects. Once you load the json with ajax, you just pass it in and tell it what field to search on and some callbacks to format the results.