If you are never asked for that information in discovery, you do not have to provide it at all. If you want to have the witnesses subpoenaed for trial, you will need to file a request for a witness subpoena more than 10 days before trial, and that request will be in the court's file to be seen, but you have no obligation to provide that information if it is not requested in discovery.
Sounds like you've decided to appear pro per. For the most part, this is not a great idea.
As to whether you have to provide any information or not is really dependent on the rules of civil procedure in your state. For example, in California, if the other side does not ask for a particular document, you have no obligation to produce it of your own accord. Before trial, you must submit witness lists and an evidence binder to the court, depending on the particular venue your case is pending in. In addition, judges may have their own rules as to how they want this information presented at the time of trial, when the the deadline is for presenting it to the Court and exchanging it with other parties involved. Arizona, on the other hand, requires disclosure of all witnesses and all relevant documents at the outset of the case. Thereafter, you have 30 days to supplement the disclosure every time you come across a new piece of evidence or new witness relevant to your case.
In short, it depends on what Virginia's Rules of Civil Procedure require. Again, you should probably consult an attorney before proceeding further so as not to jeopardize the admissibility of any documents and/or witness testimony at trial, should your case proceed further.
If you are in Circuit Court in Virginia--you need a lawyer.
If you are in General District Court, and the matter is contested (i.e. the defendant disputes your claim) the court will order a Bill of Particulars--where you lay out every element of your complaint. That will clue the defendant in to what evidence you may have and how to respond with an Answer.
I agree with attorney Matirosyan. Depending on what court/county your case is filed in, there will be Civil Procedures you must adhere to—no point in covering them all in this online forum—suffice it to say they can be confusing, complex and positively Labyrinthine to a first time non attorney litigant. If your case is complicated by witnesses, evidence for which you need to establish a foundation and have the court enter without or over the objection by defendant and or the dollar sum is significant, you should see an attorney before you proceed much further—you’d hate to lose the case because you didn’t know of a procedural hoop you needed to jump through.
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