Most people still think of AI assistants as tools that help you find things — not buy them. MoonPay just moved to change that. The company has launched PayBox, a new AI payment vault that lets users connect their crypto wallets and payment cards directly to ChatGPT and Claude, enabling purchases to happen inside a conversation without handing over control of their funds to anyone.
Summary
Key takeaways
- MoonPay’s PayBox is a non-custodial AI payment vault integrating with ChatGPT and Claude via a custom connector for in-conversation transactions.
- Users choose between “Always Ask” mode (passkey approval per transaction) or “Autonomous” mode (AI acts within user-defined spending limits).
- Wallet keys are protected using multi-party computation (MPC) and trusted execution environments (TEEs), so no single party — including MoonPay — holds a complete private key.
- PayBox supports Solana and seven EVM-compatible blockchains, with DeFi features including token swaps and perpetual futures trading planned within the next month.
- The x402 payment standard, originally developed by Coinbase and now governed by the Linux Foundation, underpins PayBox’s cross-service transaction capability.
MoonPay Introduces PayBox for AI-Driven Payments
The basic idea behind PayBox sounds simple enough: ask your AI assistant to book a restaurant, and it actually books it — including the payment. But the mechanics underneath that simplicity involve some genuinely novel engineering, and the implications for how AI agents interact with financial infrastructure go further than a booking app.
Integration with ChatGPT and Claude
PayBox connects to OpenAI’s ChatGPT and Anthropic’s Claude through a custom connector. Once installed, the AI assistant can prepare transactions — covering use cases like flight bookings through BRIJ.fi, restaurant reservations via AgentRes.dev, and online shopping through Purch.xyz — while the user retains final say over whether funds actually move.
The vault works with any merchant or service that accepts x402, an agent payment standard originally built by Coinbase and now governed by the Linux Foundation. That standard is backed by more than 20 organizations, including AWS, Cloudflare, Visa, Mastercard, Stripe, Shopify, and Anthropic, which gives it meaningful infrastructure reach even at launch.
MoonPay Labs Chief Engineer Neeraj Prasad told The Block that the product is designed to let consumers use AI for commerce without giving the assistant direct control over wallet keys, card details, or account credentials — a distinction that matters enormously given the pace at which AI agents are being handed broader digital permissions.
User Payment Approval and Autonomous Modes
PayBox offers two distinct permission models, and the choice between them reflects how much trust a user wants to extend to their AI assistant.
The “Always Ask” mode requires passkey approval for every individual transaction — nothing moves without an explicit user sign-off. The “Autonomous” mode flips the dynamic, letting the AI complete transactions independently, but only within spending limits the user has pre-defined. Each passkey approval is valid for exactly one transaction, meaning a captured or replayed authorization cannot be recycled to authorize subsequent payments.
That single-use approval mechanism is one of the more thoughtful security details in the design. It closes a specific attack vector that tends to be overlooked in payment systems built for speed.
Security and Custody Architecture of PayBox
The security architecture of PayBox is where the product makes its most important claims — and where the engineering decisions carry the most weight.
Non-Custodial Vault Combining Crypto Wallets and Payment Cards
PayBox is explicitly non-custodial. MoonPay does not take possession of user funds, and neither does the AI assistant. The vault combines crypto wallets and payment cards in a single interface without any transfer of ownership or custody to third parties. According to MoonPay, no party — including the company itself — can independently access a user’s funds or credentials.
That non-custodial design is not just a marketing point. In the context of AI-driven transactions, where an agent may be initiating activity autonomously, the question of who ultimately controls the money becomes legally and practically significant. PayBox’s architecture is built to ensure the answer remains: the user.
Wallet Key Protection and Card Payment Security
Crypto wallet keys are secured using multi-party computation (MPC) and trusted execution environments (TEEs). Keys are split across hardware-isolated secure environments, meaning no single device, session, or party — including MoonPay or the AI assistant — holds a complete private key or can sign transactions independently. The system runs on infrastructure from Sodot, a key management company MoonPay acquired earlier this year.
For payment cards, PayBox integrates Visa’s agentic commerce protocol. This allows an AI agent to initiate card purchases without ever accessing or storing the underlying card number, reducing exposure at the data layer where card fraud most commonly originates.
Technical Support and Ecosystem Integration
Blockchain Networks Supported
At launch, PayBox supports Solana and a range of Ethereum Virtual Machine-compatible blockchains: Ethereum, Hyperliquid, Tempo, Base, Robinhood Chain, Arbitrum, and Polygon. Additional networks are planned. The breadth of supported chains at launch positions PayBox to serve users across the major ecosystems where DeFi activity is already concentrated.
x402 Payment Standard and Merchant Integrations
The x402 standard functions as the connective tissue between PayBox and the broader merchant ecosystem. Originally developed by Coinbase, it provides AI agents with a common method for requesting and completing payments across online services. With backing from over 20 organizations and governance now under the Linux Foundation, x402 has the organizational scaffolding to support wider adoption — though how quickly merchants integrate it will largely determine how useful PayBox becomes in practice.
User Onboarding and Future Developments
Setup Process and Identity Verification
Getting started with PayBox involves installing the vault inside ChatGPT or Claude, creating an account, registering a passkey, and then either creating or importing a crypto wallet. Payment cards can be added optionally. Funding the vault via card requires completing MoonPay’s identity verification process first.
Planned Expansion into New AI Platforms and DeFi Features
MoonPay plans to extend PayBox support to additional AI platforms within the next month. More significantly, the company intends to add DeFi functionality — including token swaps, perpetual futures trading, and liquidity management — under the same user-defined approval framework.
That expansion is worth watching closely. Shopping and flight bookings carry low stakes if something goes wrong; perpetual futures trading and liquidity positions do not. Bringing those activities into a conversational AI interface under autonomous spending limits is a fundamentally different risk proposition than booking a dinner reservation, and it signals that MoonPay sees PayBox as a full financial interface rather than a consumer convenience tool.
PayBox sits at the intersection of several trends that have been converging for months: AI agents gaining transactional access, crypto wallets becoming consumer-facing, and payment networks like Visa investing in infrastructure designed specifically for machine-initiated commerce. MoonPay’s broader AI stack — which now includes MoonPay Agents, the Open Wallet Standard, the MoonAgents Card, and acquisitions of Entendre and Dawn Labs — suggests the company is building toward a future where the payment and custody layer is specifically designed for AI to operate within. Whether users are ready to extend that level of trust to a conversational assistant, especially for complex financial operations, may be the more telling test than the technology itself.
FAQ
How does PayBox integrate with AI assistants like ChatGPT and Claude?
PayBox connects to ChatGPT and Claude through a custom connector, enabling the AI to prepare transactions that the user then approves with a passkey. No funds move until the user confirms, unless the user has enabled autonomous mode with pre-set spending limits.
What security measures does PayBox employ to protect user funds?
PayBox uses multi-party computation (MPC) and trusted execution environments (TEEs) to split wallet keys across isolated systems, ensuring no single party can access or move funds independently. For card transactions, Visa’s agentic commerce protocol allows purchases without exposing the underlying card number. Each passkey approval is valid for one transaction only, preventing replayed authorizations.
Which blockchains does PayBox currently support for transactions?
PayBox supports Solana and seven Ethereum Virtual Machine-compatible blockchains: Ethereum, Hyperliquid, Tempo, Base, Robinhood Chain, Arbitrum, and Polygon. Additional networks are planned.
What are the user permission options for authorizing transactions with PayBox?
“Always Ask” mode requires passkey approval for every individual transaction. “Autonomous” mode allows the AI assistant to complete transactions independently, but only within spending limits the user has defined in advance.
Article produced with the assistance of artificial intelligence and reviewed by the editorial team.
