I had to call Chase about an issue with my credit card. I called them and knew I was talking to a legit agent. At least as sure as one can ever be. Still, at one point she asked me to read back the code she texted me. I started to do so then stopped. I explained that the text she sent me specifically states "We will never ask you for this number (over the phone". I refused to read it back since it violated their own stated policy.

She had to do some additional work to resolve my issue but it did get fixed.