Why are my Pole Bean Leaves drying and curling at the tips? Zone 8 zip 94903
Without seeing the beans it's difficult to accurately diagnose the problem. Beans are susceptible to spider mite feeding damage that can cause the type of browning that you describe. Check the undersides of the leaves very closely for tiny crawling mites. They are scarcely visible to the naked eye. If they are present, you can control them in one of several ways. Often a forceful water spray is enough to wash them off the plant. Or use insecticidal soap to control them.
Lack of moisture and/or hot, drying winds could also cause tip browning on beans.