/**
 * [INPUT]: MemoryEntry/Episode/WorkEntry, project, context tags, config weights
 * [OUTPUT]: retrieval score (Stanford: Recency + Importance + Relevance)
 * [POS]: Core ranking algorithm — used by engine for injection budget allocation
 *
 * Key innovation: uses per-entry adaptive strength (not global half-life)
 * for Recency, implementing Ebbinghaus spaced repetition.
 */
import type { Episode, MemoryEntry, WorkEntry } from "./types.js";
export declare function daysSince(iso: string): number;
/** Ebbinghaus decay: R = e^(-t * ln2 / S) where S = per-entry strength */
export declare function decay(ageDays: number, strength: number): number;
export declare function extractTags(text: string): string[];
export declare function tagOverlap(a: string[], b: string[]): number;
export interface ScoreWeights {
    recency: number;
    importance: number;
    relevance: number;
}
export declare function scoreEntry(e: MemoryEntry, project: string, ctx: string[], defaultHalfLife: Record<string, number>, weights: ScoreWeights): number;
export declare function scoreEpisode(ep: Episode, project: string, ctx: string[], defaultHalfLife: Record<string, number>, weights: ScoreWeights): number;
export declare function scoreWorkEntry(w: WorkEntry, project: string, ctx: string[], defaultHalfLife: Record<string, number>, weights: ScoreWeights): number;
/** Budget-constrained top-k selection by score */
export declare function pickTop<T>(items: T[], scoreFn: (t: T) => number, lenFn: (t: T) => number, budget: number): T[];