Let me share my thoughts about fortune-telling.
Fortune-telling by itself is not really harmful, something like
sex, but unlike drugs. However without the right motivation
and right understanding, fortune-telling can become harmful; as in
being manipulative, too edgy, too picky with people and things,
fatalistic, etc...
Among the numerous titles of Buddhist scriptures, there is one
Buddhist scripture that describes a method similar to
fortune-telling.
http://www.fofaseng.cn/books2/1263.htm (地藏占察善恶业报经
or Sutra on the Divination of the Effect of Good and Evil
Actions)
Remember Buddhism is not about fatalism or determinism per se,
but more about understanding profoundly what are things we can or
should change in order to achieve lasting happiness. In that sense
we also strive to recognise and understand what we cannot or should
not change.
Liao Fan Shi Xun mentioned about a very accomplished
but morally sound fortune-teller who tells things as they
are; not to extract money or obtain power from those who approach
him.
The fortune-teller practises Huang Ji Shu - which the later
Huang Ji Jing Shi Shu was based on.
《皇极声音数》
此数理前面已经谈到了，是由陈抟祖师根据36声音字母配合其他数理独创而成。全称为《皇极声音数》，也叫做《皇极数》。而后来的宋朝易学家邵康节所著《皇极经书》中的“观物篇”，便是由《皇极声音数》的数理演变而成。
至于说到太华派《皇极数》的相关推命事例，早在袁了凡所写的《了凡四训》中，就可见一斑，其中：为袁了凡用《皇极数》数推命的孔道人就是邵康节的门徒。而后来渡化袁了凡，并指点他修炼、弘扬佛法的云谷禅师，就是陈抟祖师的化身。
The above very briefly describes the history of Huang Ji Shu and
its role in ancient real-life accounts such as Liao
Fan.
Do note that the Buddha made perfectly accurate predictions
or revelations about the spiritual developments of
many of his great disciples at appropriate times. One can refer to
the Lotus Sutra in which for some chapters, the
Buddha gave predictions of future Buddhahood to many of his
disciples listening in. He did not have to resort to any kind of
fortune-telling simply because he is a fully enlightened one.
Even Arahants have the same ability - only less powerful in
terms of being only able to see 500 lifetimes into the past and
future. The Buddha's ability is that of being able to see into
countless lifetimes both in the past and future.