import type { EmbeddingProvider, VectorDocument, VectorSearchOptions } from '../hallucination/retrieval.js';
/** Every document's vector, in order, embedding the ones without a vector in one batch. */
export declare function vectorsFor(documents: readonly VectorDocument[], embed: EmbeddingProvider, dimensions: number): Promise<number[][]>;
/** Refuses a vector whose width does not match the store's, before it reaches the database. */
export declare function assertWidth(vector: readonly number[] | undefined, dimensions: number): asserts vector is number[];
/**
 * A search's `topK`, or 5 when it has none. Anything but a positive integer is refused here, because
 * some stores place the limit in a query string, where a crafted value could change the query.
 */
export declare function searchLimit(topK: number | undefined): number;
/** Checks a store's `dimensions` option. */
export declare function assertDimensions(dimensions: number): void;
/** The prefix that marks a copied metadata field in stores that filter on flat fields. */
export declare const META_PREFIX = "meta_";
/**
 * A chunk's top-level string, number, and boolean metadata, copied under `meta_` names, which is what
 * stores with flat, typed payloads filter on. The whole metadata travels separately as JSON, so
 * nested values still come back.
 */
export declare function filterFields(metadata: Record<string, unknown> | undefined): Record<string, string | number | boolean>;
/** A search's filter entries, or none when the filter is empty. */
export declare function filterEntries(filter: VectorSearchOptions['filter']): Array<[string, string | number | boolean]>;
/** Parses metadata stored as JSON, tolerating a missing value. */
export declare function parseMetadata(value: unknown): Record<string, unknown> | undefined;
/** A stable UUID for a chunk id, from the first 16 bytes of its SHA-256, shaped as version 5. */
export declare function stableUuid(id: string): Promise<string>;
/** What a JSON-over-HTTP store needs to make one request. */
export interface JsonRequest {
    fetch: typeof globalThis.fetch;
    url: string;
    method: string;
    headers: Record<string, string>;
    body?: unknown;
    timeoutMs: number;
    /** Returned instead of throwing when the server answers 404. */
    notFound?: unknown;
    /** Builds the error thrown for a status that is not 2xx. */
    error: (message: string, status: number, body: string) => Error;
}
/** Sends a JSON request with a timeout and returns the parsed body, or `undefined` when it is empty. */
export declare function requestJson(request: JsonRequest): Promise<unknown>;