/**
 * Request checks for the HTTP transport.
 *
 * The server is meant to be reached by MCP clients, on this machine or across
 * the network, so the Host header is not checked: a client on another machine
 * sends the server's own address or name there. What it must keep out is a web
 * page in someone's browser. A page can reach the server two ways: a cross-site
 * POST (a text/plain body with "application/json" in a parameter passes the
 * SDK's content-type check without a CORS preflight) and DNS rebinding (the
 * attacker's hostname re-resolves to the server, so the page can also read the
 * response). Browsers send an Origin header on every POST, and in both cases it
 * names the attacker's site, so refuseForeignOrigins answers a request only when
 * it has no Origin (MCP clients that are not browsers send none), a loopback
 * Origin, or one listed in MCP_ALLOWED_ORIGINS.
 *
 * requireBearerToken is the opt-in shared secret (MCP_HTTP_TOKEN) for a server
 * that other machines can reach.
 *
 * MAX_MCP_MESSAGE_BYTES is the /mcp body limit. It matches the SDK's stdio
 * message cap (STDIO_DEFAULT_MAX_BUFFER_SIZE), so a tool call that fits on one
 * transport fits on the other. refusePayloadTooLarge answers a body over it,
 * refuseMalformedJson a body that is not JSON, and refuseUnreadableBody every
 * other body parser error, all as JSON-RPC errors instead of Express's HTML
 * error page, which carries a stack trace.
 */
import type { ErrorRequestHandler, RequestHandler } from "express";
/** 10 MiB: the largest JSON-RPC message /mcp accepts, the same as stdio. */
export declare const MAX_MCP_MESSAGE_BYTES: number;
export declare function refuseForeignOrigins(allowedOrigins: string[]): RequestHandler;
export declare function requireBearerToken(token: string): RequestHandler;
/** Turns the body parser's 413 into a JSON-RPC error; other errors pass through. */
export declare const refusePayloadTooLarge: ErrorRequestHandler;
/** Turns the body parser's JSON syntax error into a JSON-RPC parse error (-32700); other errors pass through. */
export declare const refuseMalformedJson: ErrorRequestHandler;
/**
 * Answers every other body parser error as a JSON-RPC error with the parser's status: a body that does not
 * decompress (400), an unsupported Content-Encoding or charset (415). A status that is not a client error becomes
 * a 500 with no detail. Mounted last before the /mcp route, so it never passes an error on.
 */
export declare const refuseUnreadableBody: ErrorRequestHandler;
export declare function isLoopbackAddress(address: string): boolean;
/** The one line printed when the listener is reachable from other machines and has no token. */
export declare function openListenerWarning(address: string, tokenSet: boolean): string | undefined;
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