The jQuery doc for getJSON says it takes a url as an argument. (First hit with "jquery getJSON" search using Google).
The flask doc for url_for (first hit from internet search for "flask url_for" and searching the document) offers another link for Quickstart.
The (supplied) search
function shows the pieces in action (no google required :)
function search(query, syncResults, asyncResults)
{
// get places matching query (asynchronously)
var parameters = {
q: query
};
$.getJSON(Flask.url_for("search"), parameters)
.done(function(data, textStatus, jqXHR) {
I hope this helps.