/**
 * Hybrid Retriever
 *
 * Combines graph traversal with keyword-based search for comprehensive
 * knowledge retrieval. Uses GraphMemoryEngine for facts and
 * GraphTraversalEngine for connected context.
 *
 * Phase: 8D (Graph Knowledge Engine)
 */
import { GraphMemoryEngine, type Entity } from './graph-memory.js';
import { type TraversalResult } from './graph-traversal.js';
export interface HybridResult {
    directMatches: Array<{
        entity: Entity;
        fact: string;
        score: number;
    }>;
    graphContext: TraversalResult;
    combinedContent: string[];
    totalEntities: number;
    searchMethod: 'keyword' | 'graph' | 'hybrid';
}
export declare class HybridRetriever {
    private graph;
    private traversal;
    private ngramIndex;
    constructor(graph: GraphMemoryEngine);
    /**
     * Hybrid retrieval: keyword search + graph expansion.
     *
     * 1. Find entities matching the query by name
     * 2. Get their current facts
     * 3. Traverse the graph N hops from matches for connected context
     * 4. Score and rank all results
     */
    retrieve(query: string, k?: number, depth?: number): Promise<HybridResult>;
    /**
     * Get connectivity score for a chunk (used by HyperTune).
     * Returns 0.0-1.0 based on how connected the related entity is.
     */
    getConnectivity(source: string, label: string): number;
    /** Score a text string against query keywords */
    private scoreMatch;
    /** Format hybrid result for display */
    static format(result: HybridResult): string;
}
