import type { HtmlDocumentContribution } from '../../../services/html/html-transformer.service.js';
import type { PageMetadataProps, PageRobotsMetadata } from '../../../types/public-types.js';
/**
 * Builds a head contribution for non-default `metadata.robots` values.
 *
 * @remarks
 * When `robots` is omitted or matches the default `index,follow` behaviour,
 * no tag is emitted (Next.js parity). Otherwise a single
 * `<meta name="robots" content="...">` contribution is returned.
 */
export declare function buildRobotsMetaContribution(metadata: Pick<PageMetadataProps, 'robots'>): HtmlDocumentContribution | undefined;
/**
 * Formats robots directives for a meta tag, or `undefined` when defaults apply.
 */
export declare function formatRobotsMetaContent(robots: PageRobotsMetadata | undefined): string | undefined;