This summary is not the rule. The rule text controls.
Discovery is the process where each side can ask the other for information and documents before a hearing. This rule says that family court judges do not have to allow full discovery automatically like in regular civil cases.
Instead, the judge decides if and when discovery is needed. A judge can order discovery on their own if they think it will help the case move forward fairly. Otherwise, one side has to file a motion asking for discovery and explain to the judge why they specifically need it.
This means you cannot assume you have the right to request documents or information from the other side just because you want them. You need to show the judge a real reason why that information matters to your case. The judge then decides whether to grant your request based on what is fair and needed for the situation.