$this error() Indicate that the notification gives information about an

$this to(string $channel) Set the Slack channel the message should be sent

$this fields(array $fields) Set the fields of the attachment.

$this action(string $text, string $url) Configure the "call to action"

$this subject(string $subject) Set the subject of the notification.

$this content(string $content) Set the content (text) of the attachment

$this cc(string|array $address) Set the recipients of the message.