From Storing Coins to AI-Driven Payments: Dissecting MetaMask's Open Currency Strategy

Bank balances are not your money: how open currency ends the closed ledger.

Written by: @FourPillarsFP

Compiled by: AididiaoJP, Foresight News

Key Points

The balance in your bank app is not money you directly hold; it is a claim recorded in the bank's ledger. This closed currency requires permission, relies on intermediaries, and is highly fragmented. Once money needs to cross systems or borders, friction immediately appears.

Open currency shifts the center of money from institutional accounts to user wallets. A wallet is not a box for storing assets; it is the key to moving assets. Based on self-custody, money becomes programmable and composable.

MetaMask is evolving the wallet into an operating system for money by layering mUSD, cards, and proxy payments. Storage, consumption, payments, and even proxy authorizations converge into the same wallet. This is the ultimate goal of the wallet—open currency.

Do you really control your money?

Open your bank app on your phone. The balance displayed in the center of the main screen makes us naturally feel that this is our money. In daily life, this belief rarely encounters problems. Salaries arrive on time, and transactions require just a few taps. In countries with well-developed financial infrastructure, user experience is almost frictionless. Therefore, most people do not question: "Do I directly own this money?"

But structurally, the balance in the bank app is not a pile of physical cash. It is more like a payment obligation from the bank recorded in the ledger. In other words, it is not like the cash in my hand but more like a claim against the bank. As long as this money is a claim on the bank's ledger, the ultimate authority to decide whether it can be moved is hard to fully belong to me.

This fact is not obvious in normal circumstances. But once faced with transfer limits or frozen accounts, the balance may appear intact, yet not a single cent can be moved. On the surface, it looks like my asset, but structurally it is a right against the bank, so the power to block or freeze also exists outside of me.

If this friction arises from the legal nature of money, we must also look at the fragmented infrastructure of money flow. Even if the account is normal and there are no limits, friction will appear once money needs to enter another system. For example, in cross-border transfers: filters that do not exist within the same currency zone begin to appear—foreign exchange, intermediary banks, fees, business days. I cannot fully control when the money arrives.

These two types of friction stem from the same structure: institutions lock my money in closed ledgers, and these ledgers are fragmented from one another. Owning money and being able to move it as I wish are two completely different things. We refer to this type of currency encountered in daily life with these characteristics as "closed currency." The bottlenecks caused by this structure are often difficult to detect; they only become clear when money crosses borders, platforms, or systems.

Can this closed structure be opened? Open currency is an attempt to solve this bottleneck. Its basic idea is to allow money to flow like the internet, no longer locked within specific institutions or borders.

What is closed currency?

To understand open currency, we first need to clarify closed currency.

First, closed currency requires permission. To move money, someone must approve it. Banks approve transfers, card organizations approve payments, and payment networks process transactions. Users press a button, but the actual movement of money is authorized within the system.

Closed currency is mediated. There is always a third party between me and my assets. The bank app is the window to the bank's ledger, the brokerage app is the screen for the broker's account system, and the payment app may have smooth UX on the surface, but underneath it is still an interface to the bank, card companies, and merchant settlement networks.

Finally, closed currency is fragmented. The money in a bank account, the money in a brokerage account, the balance in a payment app, the exchange balance, and the dollars in an overseas account all seem to be "my money," but in reality, they are scattered across different systems. Every time money needs to move from one system to another, it has to go through withdrawal, deposit, settlement, and approval processes again.

This structure is very stable. It includes consumer protection, and in many cases, funds can be recovered, and users have become accustomed to it. Therefore, simply saying "banks are fake" would actually weaken the persuasiveness of open currency. People have been using it well, and this system has been running for hundreds of years.

The real question is: in an era where money has moved through the internet, should it still remain so closed? Music has moved from files to streaming, software has left discs for the cloud, and information crosses the boundaries of portals and apps through APIs. Yet money still lies scattered in institution-exclusive ledgers. Open currency focuses on this point.

What does open currency change?

Open currency shifts the center of money from institutional accounts to user wallets.

In the world of open currency, users connect to the network using wallets. Here, the wallet is not just an app. On-chain, the wallet is an account, a login, a signature authority, and also the key to moving assets. If the bank app is the window to the ledger, the wallet is closer to the power of directly moving assets.

Of course, assets do not physically exist in the wallet. On-chain assets are recorded at blockchain addresses, and the wallet manages the private keys and signature authorities that can move these address assets. In simple terms, the wallet is not a box for holding money but the key to moving money.

Directly holding this key means self-custody. Self-custody is not just "I store it myself," but rather not putting money into someone else's account, instead using the key I hold to directly control the assets. The core of open currency is control.

The reason blockchain fits this structure is clear. It turns money into a state on a public network, rather than a record in a company's database. Anyone can see the same rules, use the same address system, and interact with the same protocols. Assets can move around the clock, can be conditionally and logically attached through smart contracts, and services can connect without permission.

This is programmable money and composable money. Money is no longer just numbers sent and received; it can combine with code, move automatically, connect with other financial protocols, and settle directly on a global network.

At this point, blockchain has transformed from an abstract technical discussion into an experience that users can perceive. For example, freelancers receiving payments from overseas clients, startups paying salaries to multi-national teams, users wanting to hold and use stablecoins outside exchanges. This also applies to internet-native economic activities such as gaming, creators, AI agents, and on-chain users moving assets in open markets around the clock. For them, what matters is that money can flow without being locked into specific banks, countries, or apps.

This structure itself is not a fully completed alternative. Self-custody gives users control but also imposes responsibility on them. Key management, phishing, erroneous signatures, recovery—all are risks that users must handle themselves. Therefore, the core issue of open currency is not just "do users directly control their money," but whether it can reduce friction in security and user experience while maintaining user control.

What does MetaMask want to do?

The center of this transformation is self-custody wallets, and MetaMask is a clear example of how wallets evolve into money platforms.

It started as a simple wallet. Before MetaMask, interacting with the Ethereum network meant dealing with command lines. Running nodes, connecting RPCs, directly handling private keys, signing transactions one by one—these were barriers that ordinary users found hard to cross. MetaMask lowered the threshold with a browser extension. Creating an Ethereum account, connecting to dapps, signing transactions became a matter of a few clicks.

As more wallets with similar structures emerged over time, the role of wallets began to change. Initially, it only stored tokens; later, it became a way to log into dapps, and then it took on functions like exchanges, cross-chain bridges, and multi-chain connections. Now, stablecoins, card payments, yield products, and derivatives are all entering the wallet. Throughout this transformation, financial functions are being absorbed into the wallet based on self-custody.

Existing fintech super apps also layer many functions. They put transfers, investments, cards, points, and loans into one app. But most still operate on the ledgers of platform accounts and partner financial institutions. Users get a convenient app, but the money remains in a closed system.

MetaMask is taking a different direction. It places the user's wallet at the center of financial activities. Whether users exchange, hold stablecoins, cross-chain, or use cards, the starting point is the user's wallet, not the platform account. This may seem like a small difference, but in the structure of open currency, it is a key point. The control of money shifts from platform accounts to user wallets.

Dollars in the Wallet: mUSD

MetaMask's mUSD showcases this direction.

There are already various dollar-based stablecoins in the market. The uniqueness of mUSD lies not in its issuance but in its ability to be processed directly within the wallet experience. Users can hold dollar-based assets in their wallets, exchange them, cross-chain, deposit them into DeFi when needed, and use them for payments.

Previously, this process was broken down into several steps. Users would buy assets on exchanges, transfer them to wallets, connect to dapps, and then transfer back to exchanges to cash out. This was already cumbersome for on-chain users and a real barrier for ordinary users. They just want to use money but have to operate like plumbers: knowing which chain to use, withdrawing to which network, what a bridge is, and why fees are needed.

mUSD consolidates these steps into the wallet. When dollar-based assets sit in the wallet and can simultaneously connect to on-chain finance and real-world payments, the wallet is no longer just a storage place but becomes a structure where storage, usage, and payment can all be completed in one wallet.

Additionally, the mUSD held in the user's Money Account can generate an annual percentage yield (APY) of up to 6%. This is not interest directly paid by MetaMask but variable returns generated when the deposited funds are automatically used in on-chain lending markets. Importantly, there is no lock-up period; users can freely spend, send, and trade these funds at any time.

On-Chain Money Enters the Real World: MetaMask Card

For open currency to truly work, it must ultimately be spendable.

Even if users manage their assets well on-chain, if they cannot buy a cup of coffee at a nearby café, the experience remains incomplete for the mass market. In real life, people care more about money that can actually be used for payments rather than financial philosophy. This is why the MetaMask card is important.

Many existing crypto cards require users to deposit assets into exchange or card company accounts. They are convenient, but they bring users back into a custodial structure. To use cryptocurrency, users ultimately hand their assets over to a third party.

The MetaMask card keeps assets in the user's wallet until the moment of payment. Users can connect the assets in their wallets to the real-world card payment network. This is the moment when on-chain assets are no longer just numbers in an investment app but become a means of payment in daily life.

This is the most direct picture of open currency. Money is still in my wallet until the moment of payment and can be used at real merchants when needed. The center for storing, managing, and consuming money has become a single wallet.

Currently, there are still practical limitations, including supported countries, issuing institutions, card networks, regulations, and merchant policies. These issues are still being resolved, so user experiences vary across different regions. Nevertheless, the direction demonstrated by MetaMask is clear: wallets are becoming the interface between on-chain assets and offline payments. At this point, wallets are no longer just "coin storage apps" but actual payment interfaces for using money.

Another Tool for Open Currency: Proxy Wallets

Now let’s look at a more future-oriented topic. Everything discussed so far has one premise: the subject moving and using money is a person.

But what if the subject spending money is not a person? When AI agents conduct research, renew subscriptions, and settle fees for each API call, this premise begins to shake. If agents need human approval for every payment with a signature popup, then it is not automation. This is precisely the bottleneck of proxy payments. Transactions need to occur at machine speed, but human decisions enter every transaction.

The simplest solution is to hand over the entire private key to the agent. But this directly undermines self-custody. Once the key is given away, the agent can use the entire wallet at will, and the user loses control. Automation comes at the cost of sacrificing the control that open currency is supposed to protect.

MetaMask is taking a different path. Smart accounts utilize account abstraction to delegate specific permissions without handing over the keys. Through ERC-7710 delegation and ERC-7715 permission requests, users can grant agents limited permissions, such as "spending up to 10 USDC per day, for a month, only to buy ETH." Within this range, agents can trade without human intervention, while the control of the entire wallet remains with the user. This is where automation and self-custody can coexist without conflict.

This structure itself is not entirely a new idea. In 2023, MetaMask proposed a similar concept in the form of "trusted sessions." After users approve session keys, transactions within that scope no longer require new signatures each time. A typical example at that time was blockchain games, where users did not want to handle wallet popups for every action. This idea, which started from gaming, has been standardized through ERC-7710 and ERC-7715, and now serves as the basis for delegating permissions to agents rather than humans.

When x402 joins this structure, the framework for proxy payments becomes complete. x402 defines machine-readable payment processes on top of HTTP. Based on ERC-7710 delegation, agents can pay on request, subscribe autonomously, and make streaming micropayments without human wallet operations. This is difficult to achieve in the world of closed currency—where every step requires human approval. A payment network where a machine sends money directly to another machine under established conditions opens up above the wallet.

One place to see this attempt is the Smart Accounts Kit hackathon co-hosted by MetaMask. A total of 321 developers and 142 submitted projects set a record for the highest number of projects in a MetaMask hackathon. The theme was applications for autonomous payments by agents, and agents also participated in the judging.

On top of open currency, wallets ultimately become the layer of permissions that agents can use to move money on behalf of humans. If the wallet is the operating system for money, proxy payments represent the moment this operating system opens up to both agents and humans simultaneously.

The Ultimate Goal of Wallets is Open Currency

Returning to the title. Wallets were initially just simple signing tools. Sending tokens, connecting to dapps, and approving transactions were all they did.

But if the wallet is the key to moving user assets, more financial functions will naturally build upon it. Exchanges, cross-chain, stablecoins, yield products, card payments, multi-chain functions, and derivatives trading will all enter the wallet. This is not just a simple list of functions but the process of the wallet becoming the operating system for money.

In the world of closed currency, financial apps are windows to institutional systems. In the world of open currency, wallets are the starting point for users to directly handle money on the network. The question is not whether wallets will completely replace banks. The point is that a new option has emerged. Existing finance will continue to handle everyday domestic payments well. However, global, programmable money that can move across apps and protocols requires a different structure. Wallets are at the center of that structure.

If the balance in the bank app is a number in the ledger, the on-chain wallet is the key to directly moving assets. Closed currency brings users into the system, while open currency allows users to freely move between systems with their own wallets.

This is why the ultimate goal of wallets is open currency. Token storage, dapp logins, NFTs are just intermediate stops. The endpoint is a new layer: users directly control their money and move it freely, allowing money to flow like the internet.