From the release:
One of the most iconic magic items associated with fantasy roleplaying games since their earliest days, and one that has seen incarnations in every edition of the game for which 5th Edition is the latest version, is the Bag of Beans. This item is, of course, inspired by the magic beans that appear in the classic fairy tale commonly known as Jack and the Beanstalk. Only one magical power is associated with the beans in that story, namely growing a massive vine that stretches up into a cloud kingdom inhabited by Giants, but the creators of the world’s greatest and oldest RPG cannily realized that any number of powers might be associated with legumes of this sort and proceeded accordingly when putting them into game terms.
Many players think that the Bag of Beans is a joke, an aberration from old school editions that exists only to screw over their characters, and they are not altogether wrong. The table of effects for the 5th Edition version of this magic item is not just skewed toward harming characters, it is overly fickle and not even particularly fun and practically begs for new and more interesting effects that go beyond the mere dozen it provides.
With that need in mind, this 5th Edition sourcebook contains a replacement table with a full 100 possibilities in order to make this item more fun, unpredictable, and possibly even useful.