Is it possible to give reasons?

At work, I have to record my actions, and the reasons I took for those actions. Like with all things, this immediately leads to an existential crisis.
I can write down things that are "Facts". I can write down what I observe (or perceive) and I can write down the actions I take in response to those observations. However, to provide a reason for those actions would be impossible.
You might be thinking "ok, smartass, those observations are your reason". However, if two people have the same observations, there is slim to no chance of them taking the same actions, proving that if they are "reasons" then they are unreasonable reasons.
This leads down the rabbit hole to cause-and-effect thinking on a broader scale, which is one of those fundamental philosophical questions. What does it mean that a causes b?
I have been considering the alphabet. If I were in the alphabet, I could very well determine that b follows a. Within the context of the alphabet I could never disprove that b follows a. Applying the principle of parsimony makes it likely that some living in that world would suggest that a causes b (or perhaps that c causes b for those contrarians who say you can read an alphabet both ways). So, here is my question - how can you know that a causes b?
I can write down things that are "Facts". I can write down what I observe (or perceive) and I can write down the actions I take in response to those observations. However, to provide a reason for those actions would be impossible.
You might be thinking "ok, smartass, those observations are your reason". However, if two people have the same observations, there is slim to no chance of them taking the same actions, proving that if they are "reasons" then they are unreasonable reasons.
This leads down the rabbit hole to cause-and-effect thinking on a broader scale, which is one of those fundamental philosophical questions. What does it mean that a causes b?
I have been considering the alphabet. If I were in the alphabet, I could very well determine that b follows a. Within the context of the alphabet I could never disprove that b follows a. Applying the principle of parsimony makes it likely that some living in that world would suggest that a causes b (or perhaps that c causes b for those contrarians who say you can read an alphabet both ways). So, here is my question - how can you know that a causes b?