import { JsonValue } from "@protobuf-ts/runtime";
import { RpcError, RpcMetadata } from "@protobuf-ts/runtime-rpc";
/**
 * Create fetch API headers for a Twirp request.
 */
export declare function createTwirpRequestHeader(headers: Headers, sendJson: boolean, meta?: RpcMetadata): Headers;
/**
 * Parse Twirp error message from JSON and create RpcError from the Twirp error.
 *
 * see https://twitchtv.github.io/twirp/docs/spec_v5.html
 */
export declare function parseTwirpErrorResponse(json: JsonValue): RpcError;
/**
 * Parses fetch API response headers to RpcMetaData.
 * Drops the headers Content-Type and Content-Length.
 */
export declare function parseMetadataFromResponseHeaders(headers: Headers): RpcMetadata;