Oi eric. 
I just forgot to say something in your server and bot review.

I think that its a very good idea to implement response command into your bot.
For example if you type "!npe" then the bot sends a message with a simple explanation of the NullPointerException.

Would be cool too if you can create this help messages in Discord with a command or somthing like that.
I wrote such an explanation may you can paste this as your first Command response.
===================================================
Message:
Seems like you got a NullPointerException. In this case anywhere in your program you try to use a value that is null.
Your Exception may look like this:
Exception in thread "main" java.lang.NullPointerException
        at HelloWorld.start(HelloWorld.java:6)
        at Main.main(Main.java:4)


[Tipp] You can find a manual how to read a stacktrace here: https://stackoverflow.com/questions/3988788/what-is-a-stack-trace-and-how-can-i-use-it-to-debug-my-application-errors
Now you have to look at your stack trace. In the "caused by section" you can find the class and line where your error is. In this case:
at HelloWorld.start(HelloWorld.java:6)

This garbage is trying to say: Class => HelloWorld, Method => start(), Line => 6. 
This line:
            person.greet();


In line 6 there is only one value that could be null. This value is the person.
public class HelloWorld {
  private Person person;
  public void start() {
    person.greet();
  }
}


Obviously person is null. In this case you can fix the exception by simply adding a value to person.
If you cant assign a value to the method you can also check if the value is not null.

Example:
Person person = getPersonByName("_");
if(person != null) {
  person.greet();
}


After this tutorial you can fix the most NullPointerExceptions (or NPE) yourself!

[Tipp] You can also read the java docs to see in what case a method returns null.
Stack Overflow
What is a stack trace, and how can I use it to debug my application...
Sometimes when I run my application it gives me an error that looks like:

Exception in thread "main" java.lang.NullPointerException
at com.example.myproject.Book.getTitle(Book.java:16)
...

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