import type { Request, RequestHandler } from "express";
import type { TollgateConfig } from "./config.js";
/**
 * Best-effort client IP for Onramp Secure Init.
 * Prefer Express `req.ip` (honors trust proxy when PUBLIC_BASE_URL is https).
 * Never trust a client-supplied body field for IP.
 */
export declare function resolveClientIp(req: Request): string;
/**
 * POST /x402/session-token — mint Coinbase Onramp session token with server CDP keys.
 * Body: `{ addresses: [{ address, blockchains? }], assets?: string[] }`
 * Secrets never leave the server; browser only receives the short-lived token.
 */
export declare function createSessionTokenHandler(config: TollgateConfig): RequestHandler;