/** Writes one JSON line back to the connection a request arrived on. */
export interface JsonLineReply<Res> {
    send(message: Res): void;
}
export interface JsonLineServerOptions<Req, Res> {
    /** Log scope. */
    name: string;
    /** `postmortem` cleanup label. */
    cleanupLabel: string;
    /** Idle window (nothing {@link JsonLineServer.busy}, no request received) after which the process exits. */
    idleMs: number;
    /** Stdout line announcing the bound endpoint. */
    banner(endpoint: string): string;
    /** Handle one parsed request line; `reply` reaches only the requesting connection. */
    onRequest(request: Req, reply: JsonLineReply<Res>): void;
    /** Runs synchronously as stop begins, before connections and the listener close. */
    beforeStop?(): void;
    /** Runs once during stop, after the listener closes. */
    onStop?(): Promise<void>;
}
/**
 * Newline-JSON request loop over a native {@link IpcServer}: the server half of
 * the machine-shared workers (`shared-worker.ts` is the client half;
 * `mlx-server.py` mirrors it in Python) and of the text-prediction daemon.
 * Owns one endpoint — binding, owner-only permissions, and taking over a
 * crashed predecessor's socket are native; a live owner makes {@link serve}
 * reject with `EADDRINUSE` — feeds every connection's request lines to
 * `onRequest`, and exits the process once idle.
 */
export declare class JsonLineServer<Req, Res> {
    #private;
    constructor(options: JsonLineServerOptions<Req, Res>);
    /** Bind `endpoint` and serve until idle exit or {@link exit}; resolves once the endpoint is released. */
    serve(endpoint: string): Promise<void>;
    /** Count `work` as in flight, holding off idle exit until it settles. */
    busy<T>(work: () => Promise<T>): Promise<T>;
    /** Release the endpoint, then exit the process. */
    exit(reason: string): void;
}