import { type Hex } from "viem";
/**
 * Load-or-create the EVM session key and cache it so the synchronous
 * getOrCreateWalletKey() below can serve it. Call once at capability entry.
 */
export declare function ensurePolymarketWallet(): Promise<void>;
/** The local EVM private key (0x…), cached. Mirrors blockrun-mcp's sync helper. */
export declare function getOrCreateWalletKey(): Hex;
/**
 * USDC balance in whole dollars for `address` on the given chain. Only "base" is
 * supported (the agent's x402 wallet); Solana returns null since Polymarket
 * funding always sources Base USDC. Read-only viem call, best-effort.
 */
export declare function getChainBalance(chain: "base" | "solana", address: string): Promise<number | null>;