import { RetrievalTier } from './types.js';

/**
 * Retrieval tier ladder (issue #518).
 *
 * Explicit tier ordering so callers can reason about precedence without
 * inspecting retrieval.ts internals.  The tier names are the same strings
 * used in `RecallTierExplain.tier` and in profiling spans.
 *
 * The ladder is codified here as a read-only array; consumers that need
 * "is this a valid tier?" use `RETRIEVAL_TIERS.includes(value)`.
 */

declare const RETRIEVAL_TIERS: readonly RetrievalTier[];
declare function isRetrievalTier(value: unknown): value is RetrievalTier;

export { RETRIEVAL_TIERS, isRetrievalTier };
