This site states this specific instruction directly: with a glass of water, ideally with breakfast.
Two specific details are worth following as written: a full glass of water, and pairing with breakfast specifically rather than any other meal — worth reading both as this site's stated ideal routine, not just general advice.
The word "ideally" suggests breakfast is a recommendation rather than a strict requirement — worth reading this as flexible on meal-timing specifically, while the water instruction reads as more fixed.