/**
 * In-memory LRU + TTL cache of recent investigations.
 *
 * log10x_investigate writes a record per call; log10x_investigation_get
 * reads by id. The cache lets follow-up turns reference a prior report
 * without re-running the correlation, and lets the model cross-reference
 * pattern lists across investigations in the same session.
 *
 * Capped at 50 entries (LRU eviction) and 30 minutes per entry (TTL).
 * Without the TTL, long-running Claude Desktop sessions accumulate
 * multi-hour-old investigations forever; expiring them means a model citing
 * "investigation abc123 from earlier" gets a clean "expired" response
 * rather than stale data.
 *
 * Not persistent — state dies with the process. That's fine: MCP
 * conversations are per-process and this is session-local memory.
 */
export interface InvestigationRecord {
    investigationId: string;
    createdAt: number;
    startingPoint: string;
    environment: string;
    reporterTier: string;
    shape: 'acute' | 'drift' | 'flat' | 'environment' | 'unresolved';
    /** The full markdown report returned to the caller. */
    report: string;
    /** Flattened list of pattern identities touched by this investigation. */
    patternsReferenced: string[];
}
export declare function recordInvestigation(rec: InvestigationRecord): void;
export declare function getInvestigation(investigationId: string): InvestigationRecord | undefined;
export declare function listInvestigations(limit?: number): InvestigationRecord[];
/** Clear the cache — exposed for tests. */
export declare function clearInvestigationsForTest(): void;