How do online tournaments make sure everyone is playing fairly?

Here’s a video from FunMasterMike reminding kids that honesty and integrity are part of being a good chess player:

Fair play will be taken very seriously. Every single game of an online event will be subject to review by ChessKid’s industry-leading fair play measures. If a player has violated them, he/she will be removed from the tournament, all games will be declared lost, no refunds will be given, and possible further action can be taken. Parents, your role as stewards of proper behavior is vital. We greatly encourage you to have a talk with your child about this before the event.

A reminder of things that are not allowed when playing online chess: No computer assistance, no human assistance, no watching the live stream, no tablebases, no databases, no books, no notes, no pastgames or scorebooks, no use of a second chess set to analyze variations. In addition, no other programs of any kind are allowed to be open on your child’s computer, and only one browser tab is allowed to be open. If other tabs or programs are found to be opened, this constitutes a “technical violation” and your child will also be removed from the tournament and all games declared lost.
Being on Zoom is not necessary for this tournament.

By playing in this tournament, you are agreeing to all of these fair play rules, and you also agree to accept the final conclusions ChessKid renders about fair play.