[mgiannopoulos]

Take a look at Beeminder [1] Each goal includes an open text "fine print" where can put anything like what you describe above.

[1] https://www.beeminder.com/

[dreeves]

Thank you so much for that plug! The author of the article, alexvermeer, is also a longtime Beeminder fan! See https://alexvermeer.com/beeminder/