/** Exact, bounded facts computed from a complete array, never sampled rows.
 * They let an agent answer boolean-count questions without reading an elided tail.
 */
export declare function nullFacts(rows: readonly unknown[]): string;
export declare function booleanFacts(rows: readonly unknown[]): string;
/** Keep complete rare boolean populations, including their identifiers and
 * neighboring fields. Counts alone cannot answer which records need attention.
 * Bound both fields and population size; never sample a population and call it
 * complete. Missing/null/string values are not boolean false.
 */
export declare function rareBooleanRows(rows: readonly unknown[]): Set<number>;
/** Retain complete rare categories without knowing the user's target vocabulary.
 * High-cardinality IDs are rejected. Each admitted population is complete and
 * counted before elision; a shared row budget and group cap bound the output.
 */
export declare function rareStringGroups(rows: readonly unknown[]): {
    keep: Set<number>;
    facts: string;
};
//# sourceMappingURL=json-facts.d.ts.map