the atheist goes first

Complete intellectual honesty requires a serious consideration of there being a God of some sort. It goes back to that critical question that must be answered in a rational fashion: How do you get something from nothing? This question is so foundational and obvious that it puts the ball in the atheist's court.

Until you can make a principled, reasonable case for something to be created from nothing, you must always rely on technique rather than logic. Examples of technique used by atheists might be aggressively questioning the God-believer (theist) and taking the offensive, defaulting to an emotional appeal, or falling into logical fallacies.

Now, when it comes to a specific God, then it is the theist’s turn to make the case in the same principled, reasonable way. A “creative agent” does not automatically turn into the God of the Bible.

So, I would argue the atheist is required to provide the evidence there is no God and the theist is required to make the case for a specific God.