type RelayOptions = {
    /** Port the relay listens on (App Platform injects PORT). */
    port?: number;
    /** Shared secret the dev client must present (?token=). */
    token: string;
    /** Public base URL the relay is reachable at. Falls back to the request
     *  origin when omitted (App Platform: set APP_URL or pass explicitly). */
    publicUrl?: string;
    /** How long to wait for the dev client to answer a forwarded request. */
    requestTimeoutMs?: number;
};
type ControlSocketData = {
    control: true;
};
type PublicSocketData = {
    control: false;
    id: string;
    url: string;
    headers: Record<string, string>;
};
type SocketData = ControlSocketData | PublicSocketData;
/**
 * Start the public reverse-tunnel relay. Holds one dev-client control socket
 * and forwards every other inbound HTTP request — and public WebSocket — down
 * it. Single-tenant: the shared `token` gates the control channel.
 */
export declare const startTunnelRelay: (options: RelayOptions) => Bun.Server<SocketData>;
export {};