A "cautionary note" is a phrase that indicates a warning or advice to be careful about something. It tells you to be cautious or mindful because there may be potential risks or problems involved. Full definition
She also relates cautionary notes about the scope of the challenge. (educationnext.org)
A top attorney in the cryptocurrency space, once involved with setting up the Tezos Foundation, has issued sharp cautionary notes for those who wish to dabble within the burgeoning initial coin offering (ICO) market. (cryptotimes.news)
A few hours ago, the Reserve Bank of India decided to issue a new cautionary note on digital currencies, and of course, bitcoin. (coinshost.com)