import type { ChatAttachment } from '../chatAttachments';
/**
 * Normalizes a potentially invalid attachments payload from the client request.
 *
 * Invalid items are skipped and duplicate URLs are de-duplicated.
 *
 * @param {unknown} rawAttachments - The raw attachments to normalize.
 * @returns {Array<ChatAttachment>} The normalized attachments.
 *
 * @public exported from `@promptbook/core`
 */
export declare function normalizeChatAttachments(rawAttachments: unknown): Array<ChatAttachment>;