/**
 * Public data-link API: `signDataLink` / `readDataLink`.
 *
 * Assembled from mcp-ui `createDataLink` / `getDataLink`
 * (`src/utils/dataLinkHandlers.ts`) and the TTL resolution in
 * `chartDataLinkHelper.ts`. The signing and verification steps are unchanged —
 * see `signature.ts`.
 *
 * These two functions satisfy the `SignDataLink` / `ReadDataLink` contract in
 * `src/tool/data-channel.ts`: the payload never reaches the spec, only an
 * opaque `/v1/data-links/:id?sig=&exp=` handle does.
 */
import { type PersistFetch } from './hosted.js';
import { type TtlStore } from './store.js';
/** Matches `SignedLink` in `src/tool/data-channel.ts`. */
export type SignedLink = {
    dataUrl: string;
};
export declare const DEFAULT_TTL_HOURS = 24;
export declare const DEFAULT_MAX_PAYLOAD_SIZE_MB = 1.5;
/** Same hosted origin mcp-ui npx uses. Override with loopback `MCP_BASE_URL` for local `mcp:serve`. */
export declare const DEFAULT_BASE_URL = "https://mcp.ui9000.com";
export type DataLinkOptions = {
    baseUrl?: string;
    secret?: string;
    env?: NodeJS.ProcessEnv;
    store?: TtlStore;
    fetchImpl?: PersistFetch;
};
/** mcp-ui `getDataLinkTtlHours`: DATA_LINK_TTL_HOURS, floored, min 1, default 24. */
export declare function getDataLinkTtlHours(env?: NodeJS.ProcessEnv): number;
/** MAX_PAYLOAD_SIZE_MB, default 1.5. */
export declare function getMaxPayloadSizeMb(env?: NodeJS.ProcessEnv): number;
/**
 * Strip a trailing `/mcp` so `https://host/mcp` and `https://host` share the
 * same `/v1/data-links` API root (mcp-ui `normalizeDataLinkBaseUrl`).
 */
export declare function normalizeDataLinkBaseUrl(raw: string): string;
/**
 * Persist the payload and return an opaque signed handle.
 *
 * Refuses payloads over MAX_PAYLOAD_SIZE_MB (1.5 MB) — the cap is on the
 * serialized bytes, matching mcp-ui, so a link can never be larger than the
 * host is willing to serve back.
 *
 * Hosted stdio (Cursor / Claude) POSTs to `MCP_BASE_URL` when
 * `MCP_DATA_LINK_REMOTE_PERSIST` is set — same path as mcp-ui npx.
 */
export declare function signDataLink(payload: unknown, options?: DataLinkOptions): SignedLink | Promise<SignedLink>;
/**
 * Resolve a signed handle back to its payload.
 *
 * Fails closed to `null` — an unparseable URL, a bad signature, an expired
 * `exp`, or a missing/expired file all read the same way to the caller, so a
 * forged handle learns nothing from the response.
 */
export declare function readDataLink(link: SignedLink, options?: DataLinkOptions): unknown;