Why is phpStorm highlighting Exception?

Question

phpstorm

There is a validation function that processes the file. PHPStorm why highlights exceptions
for clarity, I made a screen in which you can see how the storm reacts and what error it writes

. Although I process these exceptions when calling, please tell me what he doesn’t like?

try{
    $this->validate($file_csv);
}catch (\Exception $e){
    echo $e->getMessage();
    die;
}

Answer 1

Add a comment (annotation) to the validate method.
To do this, place the cursor on the line before enter and press Enter. Should workprivate function validate/**

/**
* @param $file
* @throws Exception
*
**/
private function validate ($file) {

It won't light up anymore.