import { ContentBlockParam } from '@anthropic-ai/sdk/resources/index.mjs';
/**
 * Validates if a message content is a valid Anthropic message content object.
 * If the content is a string or doesn't match the expected structure, returns null.
 *
 * @param content - The message content to validate
 * @returns The validated content object if valid, null otherwise
 */
export declare function asValidMessageContentObject(content: unknown, overrides: {
    cacheControl?: 'ephemeral';
}): null | ContentBlockParam[];