How to properly handle errors for an API response?

Question

PHP

The question arose, for a successful answer is always good and convenient to give?
For example, interrupt at:
throw new Exception(77, 'Не верный формат!')
and the answer will be:

{success: false, message: 'Не верный формат!', errorCode: 77}

or directly in the controller:

return [ "success" => false, "message" => 'Не верный формат!', "errorCode" => 77];

Answer 1

And if rest is used, then you can return just text and a 400 error.

Answer 2

I have so:

function error($string)
{
 $arr = array('answer' => 'error', 'string' => $string);
 echo json_encode($arr);
 exit;
}