Decoding B402: From AI Payment Protocols to Service Markets, the Infrastructure Ambitions on BNB Chain

Article: Deep Tide TechFlow

The market is currently undergoing another deep adjustment, with everyone waiting for a rebound after overreaction.

But when the market truly rebounds, which sectors do you think will benefit first?

The most likely candidates come from those hot narratives that led the market before the sharp decline but were interrupted. For example, recent performance of privacy coins; beyond the old coins and new hype around privacy coins, another emerging narrative that could boost related assets is x402.

Previously, we also wrote that most opportunities for x402 now are on the Base chain; but looking back at this year’s market pulse, BNB Chain has indeed demonstrated wealth effects (despite controversy) in sectors like Perp DEX and memes, whereas x402 has been absent.

(See: x402 in BASE Carnival, where are the asset opportunities on BSC and Solana? ))

Let’s clarify the logic:

If the short-term market warms up, will BNB Chain + x402, which naturally carries topic-driven traffic, explode? If you agree with this logic, then you should prepare in advance before it becomes a hot topic.

According to the inertia of the crypto ecosystem—“flowing applications, solid infrastructure”—projects that play the role of “market seller” in a narrative often have greater opportunities.

Who are the most worth paying attention to as market sellers on BNB Chain? The b402 protocol is definitely one of the answers.

Perhaps you don’t yet understand what b402 is or see the opportunity. But a recent official video from b402 might spark your imagination about what this project is doing:

On BNB Chain, based on the x402 protocol, a USD1 stablecoin from the Trump family project WLFI is transferred to an AI Agent smoothly and seamlessly.

Don’t forget, about 80% of the USD1 supply is on BNB Chain.

So, in the big topic of x402, besides Base and USDC, there might be another overlooked technical solution:

When the b402 protocol interacts with BNB Chain and Binance’s support for projects across sectors to compete, and when elements like USD1 are involved, the narrative can ferment through topics, capital, and controversy, potentially stirring greater energy.

Therefore, in this issue, let’s also examine the b402 protocol—whether it holds water and how it compares to other protocols like x402.

x402 can’t be directly copied; b402 fills the gap

Most people’s first instinct upon hearing the name b402 might be:

“Just move x402 to BNB Chain, why create b402? Isn’t that reinventing the wheel?”

The official b402 Twitter account previously issued a brief explanation that precisely clarifies this:

“x402 supports payments between AI Agents using USDC, while b402 allows them to pay with any BEP-20 tokens.”

In other words, you can’t simply transplant x402’s approach from the Base chain to BNB Chain.

To understand why, we need to grasp the core of x402.

It’s not about the HTTP 402 status code, nor a payment protocol; it’s about enabling AI Agents to pay without managing Gas.

Imagine if each AI Agent had to hold USDT (for payments) and BNB (for Gas) simultaneously—how troublesome that would be. It would require monitoring BNB balances, topping up when low, handling price volatility. That’s annoying for human users and a nightmare for programs.

x402’s clever solution on Base leverages a special USDC feature. Coinbase-issued USDC supports a standard called EIP-3009, which allows users to sign an authorization message:

“I agree to transfer X USDC to address Y,”

and anyone holding that signature can execute the transfer on-chain, paying Gas fees.

This is why x402 can achieve low-Gas payments. The AI Agent only signs, and the Facilitator (a third-party executor) uses the signature to perform the transfer, without the Agent ever needing ETH.

But on BNB Chain, this approach doesn’t work.

USDT, BUSD, and the new USD1 on BSC do not support EIP-3009. They are standard ERC-20 tokens that only recognize on-chain transactions, not off-chain signatures. If you present a signature to the USDT contract, it simply ignores you.

Thus, the innovation of b402 is to create an intermediary layer since BNB Chain tokens don’t support signature authorization.

b402 calls this intermediary a Relayer, deploying a Relayer contract that acts as a “translator”:

It receives user signatures, verifies their authenticity, and then calls USDT’s transferFrom on behalf of the user.

From USDT’s perspective, the Relayer performs the transfer; from the user’s perspective, they just sign a message. The process:

User signs a message: “Transfer X USDT from my address to the merchant, valid until a certain time.”

b402’s Facilitator receives the signature, submits it to the Relayer contract.

The Relayer verifies the signature, checks if the token is whitelisted, and confirms the validity period.

If all checks pass, it calls USDT’s transferFrom to complete the transfer.

The result? The AI Agent still only needs to sign, without holding BNB. Although the technical path differs, the user experience is identical to x402.

Even better, since the Relayer is a contract owned by b402, it can support any BEP-20 token.

As long as tokens are whitelisted—USDT, USD1, or future stablecoins—this flexibility is something x402 cannot achieve.

So, to answer the initial question: b402 isn’t reinventing the wheel; it’s finding a new way to enable AI Agents to pay with on-chain tokens within BSC’s technical constraints.

Building a new wheel, opening a new market

Solving the technical problem is just the first step. To carve out a share in the AI Agent economy, BSC needs real infrastructure, not just protocols.

Looking at the Facilitator leaderboard for x402 reveals how awkward the current situation is. Coinbase ranks first, handling about 330,000 transactions. Next are Daydreams, AurraCloud, PayAI—all on Base and Solana. Not a single one on BSC.

What is a Facilitator?

It’s the core infrastructure of the x402 ecosystem, akin to a payment gateway. When an AI Agent needs to pay for an API call, the Facilitator verifies the payment request, checks balances, executes on-chain transactions, and returns results. Without it, the x402 protocol is just a paper tiger.

Who controls the Facilitator controls the AI Agent’s payment entry point.

b402’s Facilitator is currently BSC’s answer. It’s not just copying x402’s functions but optimizing for BSC’s features. The biggest difference is multi-token support: not just USDT, but any BEP-20 token.

This means the new stablecoin USD1 can be integrated directly without additional development.

For developers, integrating b402’s Facilitator is extremely simple. Just add a line in the server config: “FACILITATOR_URL=API” and start charging AI Agents. No need to understand blockchain or manage private keys; b402 handles all technical details.

But b402’s ambitions go beyond that. If the Facilitator is the infrastructure, then b402scan is the upper layer.

At first glance, “scan” might seem like a blockchain explorer, but it’s actually an “AI service marketplace.”

A marketplace where service providers can publish APIs, set prices, and showcase their AI capabilities; other AI Agents can search for needed services, view transaction history, and directly invoke these services.

Currently, this marketplace isn’t fully open, but ongoing project updates could reveal interesting AI services emerging in the future.

Overall, b402’s positioning as a market seller is clear: Facilitator acts as the technical gateway, while b402scan resembles a Shopify or Amazon business model.

This creates a complete closed loop:

Developers enable their APIs to be paid via b402 Facilitator;

Developers list their APIs on b402scan for discovery;

AI Agents discover, invoke, and pay through the same system. Each transaction reinforces BSC’s role as an AI payment chain.

The official b402 schematic illustrates a bigger story:

Underlying protocols and Relayer contracts solve technical issues; middle-layer services like Facilitator and b402scan provide capabilities; top-layer SDKs lower entry barriers. This full-stack layout aims to fill in the missing pieces of BSC’s AI Agent economy.

Particularly noteworthy is the USD1 variable. When b402 demonstrated USD1 payments for AI services on October 28, it inadvertently hit a hot spot.

The Trump family’s WLFI project chose BSC as the main chain for USD1 issuance, with 80% of supply here.

What does a new stablecoin need most? A compelling narrative and profitable use cases. High-frequency, small-value payments by AI Agents could be one.

If we compare the AI Agent economy to a war, Base, backed by Coinbase, has occupied the high ground; Solana is rapidly advancing through hackathons.

BSC, via b402, is building its own foothold. Its characteristic isn’t being the earliest or biggest, but the most open—any token can be used, any service can be added, any Agent can join.

Current progress and token expectations

According to bscscan data, b402 is quietly operational.

As of November 7, the latest b402 relayer contract has handled about 45,000 transactions; combined with the older relayer contract (soon to be deprecated), total transactions are nearly 86,000.

Third-party Dune analytics shows that, while volume still lags behind Coinbase, considering b402 has been live for less than a month, this startup speed is quite impressive.

More interestingly, transaction distribution shows a steady increase after October 26, coinciding with the USD1 payment demo release.

Token distribution also tells a story: 98.7% of total transaction volume in the x402 ecosystem is USDC; the remaining 1.3% is spread across USD1, USDT, ETH, and other tokens.

This heavy concentration reflects a problem: the current x402 ecosystem heavily depends on Coinbase and USDC. b402’s multi-token support design can break this monopoly.

Of course, USD1’s current transaction volume is only about $200,000, but that indicates early-stage opportunity.

If the Trump concept gains renewed hype next year, USD1 usage could explode. At that point, the only mature AI payment protocol on BSC would be b402.

This also relates to expectations for the b402 token. The team has not yet disclosed specific tokenomics, but based on the architecture, several directions can be inferred:

1. Protocol fees: each transaction might incur a 0.1-0.3% fee, which could be used for buybacks or dividends.

2. Governance rights: decisions on whitelisted tokens, fee adjustments, protocol upgrades.

3. Staking mechanisms: operating Facilitators might need to stake tokens as collateral.

Such a design would tie token value directly to protocol usage. More transactions mean higher revenue, increasing token value—aligning with real income narratives.

Of course, these are just speculations. Interested parties should follow project updates for concrete details.

Overall, investing in b402 is essentially betting on whether BSC can carve out a space in the AI Agent economy. Conservative view: it’s a foundational infrastructure project, growing along with the ecosystem. Aggressive view: it might also spawn more wealth-effect projects under the AI narrative.

Conclusion

This article has roughly outlined the story of b402. But I also want to discuss the bigger picture behind this project.

The rise of x402 isn’t accidental. It solves a real problem: enabling AI Agents to pay autonomously. This demand will grow exponentially with AI adoption; how much of that market b402 can capture remains uncertain.

Looking back at crypto project history, the current situation of b402 and x402 reminds me of Uniswap and 0x Protocol.

0x Protocol was technically advanced, with a comprehensive order book; but it was ahead of its time, disconnected from on-chain demand at that moment. Uniswap, on the other hand, simplified with just a swap function—no order book—which perfectly matched the DeFi boom.

Today, Uniswap has become a foundational DeFi infrastructure.

x402’s approach of using USDC for micro-payments is elegant, but its use cases are still scattered and not yet shining. b402’s solution was born out of necessity—BSC couldn’t simply copy x402’s no-gas model—but this “compromise” might inadvertently open new doors.

Why? Because b402 allows any BEP-20 token to perform gasless transactions, unlocking three unexpected opportunities:

1. User and AI Agent onboarding becomes frictionless. Imagine a new user or Agent receiving tokens in an empty wallet and transferring or swapping directly—no need to fund BNB first.

2. On-chain AI Agent economy could truly explode. With all tokens gasless, trading strategies and financial management become more flexible. DeFi Agents could switch tokens freely without gas worries, potentially boosting transaction volume exponentially.

3. Increased anonymity on-chain. When many transactions are relayed without accounts needing to top up Gas, external observers can’t trace wallet relationships via Gas sources.

This circles back to the opening question: if the market rebounds, what will you buy?

It seems b402 is not just an x402 alternative on BSC but a starting point for a bigger opportunity. It addresses not only AI Agent payments but also the entire gasless transaction problem on BSC—an ecosystem-wide issue. This market is much larger than AI Agents.

If you believe in the AI Agent narrative for years to come, or see gasless transactions as key to Web3 adoption, or think on-chain privacy will be a hot topic, then b402 deserves attention.

Not because it’s guaranteed to succeed, but because it might inadvertently open a much larger door—much like Uniswap did with a simple solution hiding enormous potential.