* set of size {@code m x n x p}, its actual memory consumption is much smaller. When the
   * cartesian set is constructed, the input sets are merely copied. Only as the resulting set is
   * iterated are the individual lists created, and these are not retained after iteration.
   *

   * set of size {@code m x n x p}, its actual memory consumption is much smaller. When the
   * cartesian set is constructed, the input sets are merely copied. Only as the resulting set is
   * iterated are the individual lists created, and these are not retained after iteration.
   *

                    + "Select ONLY documents that DIRECTLY address the user's specific question topic. "
                    + "Do NOT select documents about different or merely related topics. "
                    + "Do NOT select table-of-contents or index pages that lack substantive content. "
                    + "Respond with JSON only. Do not include any text outside the JSON object.\n\n"