score:2
You can find the detailed routes and schedules on the official Kyoto Transport site, which makes it clear that these services are two-way. For example, here's Bus 100:
http://www2.city.kyoto.lg.jp/kotsu/busdia/keitou/kto/100.htm
Note how each stop (except the termini) has schedule links for 清水寺・銀閣寺行き (Towards Kiyomizu/Kinkaku Temples) and 京都駅行き (Towards Kyoto Station).