import type { RequestHandler } from '@sveltejs/kit';
import type { SSEManager } from '../sse.js';
export interface StreamHandlerOptions {
    /**
     * Heartbeat interval in ms. A comment line (`: heartbeat`) is sent
     * periodically to keep the stream alive through idle-timeout proxies and to
     * detect a dead socket (enqueue then throws → the connection is pruned).
     * Default 25_000 (25s). Set 0 to disable.
     */
    heartbeatMs?: number;
    /**
     * Max concurrent SSE connections per user. Requests beyond this are refused
     * with 429, bounding the file descriptors / memory a single account can
     * hold open. Default 5.
     */
    maxConnectionsPerUser?: number;
}
export declare function createStreamHandler(sse: SSEManager, options?: StreamHandlerOptions): {
    GET: RequestHandler;
};