Does anyone know a way to include an opt-out option when texting customers via text message?

I run a small collections agency and use RingCentral to allow our workers to work remotely. With the new laws coming down we are finally allowed to text consumers who request to be have information texted to them. What I would like to do is when a text is sent to automatically include opt-out instructions to the consumer. Is there a way to do that in Ring Central that I'm just not seeing?