Can authorize method in Request class return customized message for HandlesAuthorization trait?

I believe you shouldn't look at HandlesAuthorization trait. All you need to do is implementing failedAuthorization method in your request class.

In FormRequest class it's defined like this:

/** * Handle a failed authorization attempt. * * @return void * * @throws \Illuminate\Auth\Access\AuthorizationException */protected function failedAuthorization(){    throw new AuthorizationException('This action is unauthorized.');}

so all you need is to override this method in your UpdateRoleRequest class for example like this:

protected function failedAuthorization(){    throw new \Illuminate\Auth\Access\AuthorizationException('User has to be an admin.');}

To provide a solution answering @Pooria Honarmand's question for anyone else wondering the same;
If you have more specific messages for different conditions that you already checked in the authorize method and you don't want to repeat those checks here, just introduce one or more class-based variables.

Here is one example having only one condition which does result in a non-standard message:private bool $hasMissingClientId = false;

public function authorize(): bool{    // several other checks    if (empty($user->client_id)) {        $this->hasMissingClientId = true;        return false;    }    return true;}protected function failedAuthorization(){    if ($this->hasMissingClientId) {        throw new AuthorizationException('User has to be assigned to specific client.');    }    parent::failedAuthorization();}