The Open Wallet Standard aims to fill a gap in the rapidly growing agentic payments stack by giving AI agents a universal, non-custodial way to hold funds and sign transactions across blockchains.
MoonPay on Monday released the Open Wallet Standard (OWS), an MIT-licensed, open-source specification that defines how AI agents interact with crypto wallets, including key storage, transaction signing, and cross-chain account derivation, without ever exposing a private key to the agent process or the large language model driving it.
The standard launched with contributions from over 15 organizations spanning payments, exchanges, and blockchain infrastructure, including PayPal, OKX, Ripple, Tron, TON Foundation, Solana Foundation, Ethereum Foundation, Base, Polygon, Sui, Filecoin Foundation, LayerZero, and Circle.
“The agent economy has payment rails. It didn’t have a wallet standard,” MoonPay CEO Ivan Soto-Wright said in a statement.
The release arrives as the infrastructure for agentic payments is rapidly developing, yet remains fragmented across competing protocols, each assuming agents already have a wallet without specifying how that wallet should work.
As The Defiant reported last week, two protocols are racing to become the foundation of AI payments: x402, backed by Coinbase, and the Machine Payments Protocol (MPP), launched by Stripe and Tempo. Tempo’s payments-focused Layer 1, which went live on mainnet on March 18, shipped with MPP’s “sessions” primitive, allowing agents to set a spending limit upfront and stream micropayments continuously without an on-chain transaction per interaction.
On the same day, Coinbase dropped a significant upgrade to x402, adding support for virtually any ERC-20 token via Uniswap’s Permit2 and new gas sponsorship extensions.
Meanwhile, Visa entered the arena with its own approach. Visa Crypto Labs launched Visa CLI, a command-line interface payment tool targeting AI agent payments, currently in closed beta. And Circle launched Nanopayments on testnet, built on the x402 standard and designed for sub-cent, gas-free USDC transactions for AI agents paying for pay-per-call APIs.
But as MoonPay frames it, all of these systems share a common assumption: the agent already has a wallet. None defines where the wallet lives, how keys are stored, or how one agent discovers a wallet created by another.
In practice, MoonPay says, this means a user running three different AI tools today could have their funds scattered across three separate wallets with no way to access a unified balance.
How It Works
The Open Wallet Standard is structured as seven sub-specifications covering storage, signing, policies, agent access, key isolation, wallet lifecycle, and supported chains. Each module can be adopted independently.
The core design principle is zero key exposure. Keys are encrypted, decrypted only to produce a signature, held in protected memory that cannot be swapped to disk, and wiped immediately after signing. The private key is never accessible to the agent, the LLM context, or any parent application.
A single seed phrase derives accounts across eight chain families — EVM, Solana, Bitcoin, Cosmos, Tron, TON, Spark, Filecoin, and XRP Ledger — with a unified signing interface and CAIP-2 chain identifiers.
There’s also a pre-signing policy engine that evaluates every transaction before any key material is touched. Operators can set spending limits, contract allowlists, chain restrictions, and time-bound authorizations. The standard ships with native SDK bindings for Node.js and Python, a CLI, and an MCP server interface compatible with frameworks including Claude, ChatGPT, and LangChain.
The launch positions OWS not as a competitor to x402 or MPP but as a complementary layer. When x402 returns a payment request, OWS produces the signed authorization. When MPP opens a session and streams micropayments, OWS signs each payment within the agent’s authorized limits.
Whether MoonPay’s open standard gains traction will depend on whether competing agent frameworks adopt a shared wallet layer or continue building proprietary key management.
This article was written with the assistance of AI workflows. All our stories are curated, edited and fact-checked by a human.
Source: https://thedefiant.io/news/defi/moonpay-unveils-wallet-standard-for-ai-agents
