Alax request and pass Json data to Wordpress?

Question

JavaScript

Hello.
You need to pass a Json request and get a Json response from wordpress.
I'm stuck on an incomprehensible error. The chrome debugger points to the last closing brace
"Jquery.ajax" and writes "Uncaught SyntaxError: Unexpected end of input". What does he want from me?

jquery.ajax({
type: 'POST',
url: '<?php echo admin_url("admin-ajax.php") ?>',
data: {
action: 'my_action',
whatever: 1234 },
success: function( msg ){
console. log( msg );
}
//dataType: dataType
});