MoonPay’s PayBox Lets AI Agents Spend Without Taking Custody

MoonPay launched PayBox on July 29, 2026, a payment vault for AI assistants Claude and ChatGPT that lets users authorize transactions via passkey without handing custody of funds to the AI agent or MoonPay. The vault uses threshold cryptography from Sodot, which MoonPay acquired on April 29, 2026, and supports Solana, Ethereum, Base, Arbitrum, Polygon, Hyperliquid, Tempo, and Robinhood Chain, with card payments routed through Visa's agentic commerce framework.

AI Models & Platforms https://www.unite.ai/series/artificial-intelligence/ MoonPay’s PayBox Lets AI Agents Spend Without Taking Custody Add Unite.AI to your preferred sources on Google https://www.google.com/preferences/source?q=unite.ai MoonPay has put a payment vault inside Claude and ChatGPT. PayBox https://paybox.sh/ is live as of July 29, 2026, and it lets a user tell an AI assistant to swap tokens, fund a wallet, pay a merchant or hold a dinner reservation, with the money moving from the user’s own wallet or card after a passkey tap. The company announced the launch https://www.prnewswire.com/news-releases/moonpay-launches-paybox-a-payment-vault-for-claude-and-chatgpt-that-turns-prompts-into-payments-302837796.html as what it calls the first payment vault built for AI. There is no custody handoff to a hosted wallet or a platform account: MoonPay says neither the AI agent nor MoonPay itself can sign a transaction alone. Setup runs through a custom connector inside either assistant. The user registers a passkey, then creates or imports a wallet and optionally adds cards, funding the account from an existing wallet or through MoonPay’s identity-verified card ramp. Every credential then sits under one of two policy modes the user picks: Always Ask , where each transaction needs a fresh passkey approval, or Autonomous , where the agent acts inside limits the user sets. Changing those limits requires another passkey approval, and access can be revoked at any time. At launch PayBox supports Solana plus Ethereum, Base, Arbitrum, Polygon, Hyperliquid, Tempo and Robinhood Chain. Payments to services outside crypto travel over x402 https://x402.org/ , the Linux Foundation–hosted standard that uses the web’s HTTP 402 “payment required” response to let a server quote a price and a client pay it in stablecoins with no account and no API key. That rail is small but no longer theoretical: x402’s own dashboard counts 75.41 million transactions worth $24.24 million over the previous 30 days, an average of about 32 cents each. MoonPay says restaurant reservations, travel bookings and shopping at major online retailers are the first integrations working, with more added weekly. How the vault holds the keys Wallet keys are split using threshold cryptography and held inside secure enclaves, so no device, session or party holds a complete key or can sign on its own, according to MoonPay. A compromised phone, on that design, does not hand an attacker the pieces needed to move funds. The key management comes from Sodot, the infrastructure company MoonPay acquired on April 29, 2026 https://www.moonpay.com/newsroom/moonpay-institutional alongside the launch of its institutional business. MoonPay said at the time that Sodot’s technology had secured more than $50 billion in transactions and protected over 10 million wallets for clients including eToro ETOR https://www.securities.io/nasdaq/ETOR/ , BitGo BTGO https://www.securities.io/nyse/BTGO/ and Exodus. Card payments are handled differently. MoonPay says they run through Visa’s agentic commerce framework https://www.visa.com/en-us/solutions/intelligent-commerce , which lets a verified agent pass the payment details a merchant expects without the vault storing a raw card number, and that purchases can use one-time virtual cards scoped to a single merchant and amount. Each passkey approval covers one action and expires after use, which is aimed at the replay problem in agent-initiated payment fraud https://www.unite.ai/modern-ai-fraud-operational-resilience/ : an approval that cannot be reused cannot be widened into standing access. The company says the cryptography has been audited by Trail of Bits and NCC Group, and that the product meets the card industry’s PCI DSS security standard. Where the authorization rules stand The harder question is not cryptographic. It is whether a standing mandate counts as authorization under payment law written for people who click. An IMF note on agentic AI in payments https://www.elibrary.imf.org/view/journals/068/2026/004/article-A001-en.xml , published in April 2026 by Sonja Davidovic and Hervé Tourpe, frames the gap: most payment regimes require that a payment order be traceable to an authorized instruction from an account holder or its legally recognized agent, and agent-initiated payments do not always produce one. “Authorization instead becomes structural and mandate based, which raises questions about traceability, consent, and liability under existing legal frameworks,” the authors write. The architecture they recommend keeps probabilistic reasoning upstream and holds authorization and settlement to deterministic rules, which is roughly the shape of PayBox’s policy layer: the model proposes, a rules engine and a passkey decide. MoonPay is building that layer from inside a regulated perimeter, which matters for how quickly banks and card issuers engage with it. New York’s Department of Financial Services lists MoonPay Trust Company https://www.dfs.ny.gov/virtual currency businesses as holding a limited purpose trust charter granted in November 2025, on top of the BitLicense, state money transmitter licenses and EU authorization the company cites. That is a stronger supervisory position than most of the startups now shipping agent identity and trust plumbing https://www.unite.ai/ai-agents-ecommerce-payment-infrastructure/ , and it gives regulators a licensed entity to address when an agent buys the wrong thing. Who else is building this The competitive field is filling in from both ends. Stripe has already handed agents a way to pay https://www.unite.ai/stripe-hands-ai-agents-a-wallet-ushering-in-agentic-purchasing/ using tokenized access to a user’s stored methods. Robinhood and Coinbase offer their own tools for funding an agent, as Fortune reported https://fortune.com/2026/07/23/moonpay-launches-universal-ai-shopping-wallet-for-non-technical-claude-and-chatgpt-consumers/ when it previewed PayBox on July 23, 2026, and Visa and Mastercard are building agent verification into the card networks themselves. MoonPay’s pitch is that its version does not route through any single platform’s permissions. “The giants are building agentic payments inside their own walls; we’re the opposite bet: your own money, on open rails, reaching everything the walled versions can’t, from a dinner reservation to a DeFi protocol,” MoonPay Labs chief engineer Neeraj Prasad told Fortune. Next on MoonPay’s list is support for more AI platforms and a deeper push into decentralized finance, letting an agent route swaps, trade perpetual futures and manage liquidity under the same user-defined approval rules. That extends standing-mandate spending from restaurant bookings to leveraged positions, and it is where the controls a firm sets before execution https://www.unite.ai/agentic-ai-governance-risk-controls-pre-execution/ start carrying real money.