/** Raised for a document we will not send onward. The caller turns this into a clean 4xx/502. */
export declare class DocumentError extends Error {
}
export interface TranscodeOptions {
    /** Override the MarkItDown executable (default `markitdown`, or $LLM_RELAY_MARKITDOWN). */
    command?: string;
    maxBytes?: number;
    timeoutMs?: number;
    /** Injected in tests. */
    runner?: (buf: Buffer, ext: string, opts: Required<Pick<TranscodeOptions, "command" | "timeoutMs">>) => Promise<string>;
}
/**
 * True if the request carries at least one `document` content block — at the top level of a
 * turn, or nested inside a `tool_result`.
 */
export declare function hasDocumentBlocks(body: unknown): boolean;
export declare function clearDocumentCache(): void;
/**
 * Replace every `document` block with a markdown `text` block. Returns a NEW body —
 * the caller's object is not mutated. Throws `DocumentError` if any document cannot
 * be converted; there is no partial success, because a request that silently lost one
 * of its attachments looks identical to one that never had it.
 */
export declare function transcodeDocuments(body: unknown, opts?: TranscodeOptions): Promise<unknown>;