Why is the HanYu Pinyin entry method for 亅 "jue3" instead of "jue2"?
This character is not often used in China. As a Chinese person, I don't know the character until I searched it on the internet. The electric dictionary says it should be jue(3).  At last, I have to say I really didn't recognize the character. If we want to express the word "hook ", we would directly use 勾子 instead of jue (3). Hope I did help you.