import type { ArcjetDecision } from "@arcjet/protocol";
interface HeaderLike {
    get(name: string): string | null;
    has(name: string): boolean;
    set(name: string, value: string): void;
}
interface ResponseLike {
    headers: HeaderLike;
}
interface OutgoingMessageLike {
    getHeader: (name: string) => string[] | number | string | undefined;
    headersSent: boolean;
    hasHeader: (name: string) => boolean;
    setHeader: (name: string, value: ReadonlyArray<string> | number | string) => unknown;
}
/**
 * Decorable value.
 *
 * Something that looks like `Headers` (Fetch),
 * `OutgoingMessage` (Node.js), or
 * `Response` (Fetch).
 */
export type ArcjetCanDecorate = HeaderLike | OutgoingMessageLike | ResponseLike;
/**
 * Decorate something based on an Arcjet decision with rate limit headers.
 *
 * Sets `RateLimit-Policy` and `RateLimit` and conform to the
 * [Rate Limit fields for
 * HTTP](https://ietf-wg-httpapi.github.io/ratelimit-headers/draft-ietf-httpapi-ratelimit-headers.html)
 * draft specification.
 *
 * @param value
 *   Decorable value.
 * @param decision
 *   Decision from `protect()`.
 * @returns
 *   Nothing.
 */
export declare function setRateLimitHeaders(value: ArcjetCanDecorate, decision: ArcjetDecision): void;
export {};