MoonPay’s PayBox payment vault lands in Grok

MoonPay announced PayBox is now live inside Grok, enabling the conversational AI to connect to users’ self-custodial wallets, stored cards and credentials. Grok can prepare transactions — including transfers, token swaps, bridges and purchases — which execute only after the user approves them.

When Grok prepares a transaction, users review the details and approve with a scoped passkey. MoonPay says those passkeys expire after use and are restricted to the specific action authorized, preventing reuse or broader access.

PayBox is built so no single party can access a complete private key or sign transactions on its own. Card information is stored in a way that allows agents to transact without exposing raw card numbers. Wallet keys are protected using threshold cryptography (MPC) and secure enclaves (TEEs).

The vault uses key-management technology from Sodot, a company MoonPay acquired in 2026. MoonPay states Sodot’s infrastructure secures more than $50 billion in assets and over 10 million wallets and now powers every PayBox vault.

PayBox supports Solana and multiple EVM-compatible networks, including Ethereum, Hyperliquid, Tempo, Base, Robinhood Chain, Arbitrum and Polygon. The integration also implements x402, an open standard for agent-initiated payments, to let AI agents pay services built to accept those calls, such as travel bookings and restaurant reservations.

MoonPay offers two permission modes for PayBox credentials. “Always Ask” requires a passkey confirmation for every transaction. “Autonomous” allows the AI to act within limits the user sets; changing those limits requires a new passkey and users can revoke access at any time. MoonPay says PayBox is not a custody product and that funds remain under user control rather than being held by the AI or the platform.

PayBox first launched in July with support for Claude and ChatGPT. The rollout to Grok expands availability to another conversational platform as developers test agent-initiated actions beyond text responses.

Ivan Soto-Wright, MoonPay’s CEO and founder, described the Grok integration as advancing the company’s goal of enabling payments through conversational interfaces while keeping users in control of their funds.