import type { DomainId } from './domains.js';
export type RelatedReference = `concept:${string}` | `recipe:${string}` | `resource:${string}` | `tutorial:${string}`;
/** Typed metadata for one Explanation page. Markdown supplies optional prose only. */
export interface ConceptReferenceEntry {
    readonly id: string;
    readonly title: string;
    readonly domain: DomainId;
    readonly related: readonly RelatedReference[];
}
/**
 * Authoritative concept registry. A concept exists because it is declared here;
 * an optional `apps/horizon/docs/public/docs/concepts/<id>.md` file enriches its rendered
 * body and search text but never controls membership or metadata.
 */
export declare const CONCEPT_REFERENCE: Readonly<Record<string, ConceptReferenceEntry>>;