Function isAmbiguous

src/core/reranker.ts:173–181

(results: SearchResult[])

 * the embedding model isn't confident about the ranking.
 */
export function isAmbiguous(results: SearchResult[]): boolean {
  if (results.length < 3) return false;

  const topScore = results[0].score;
  const thirdScore = results[Math.min(2, results.length - 1)].score;
  const gap = topScore - thirdScore;

  return gap < AMBIGUITY_THRESHOLD;
}

/**
 * Rerank the top-K results using a cross-encoder.