x402b: Develop an auditable AI Agent payment infrastructure for BNB Chain

Introduction

Pieverse works to build payment infrastructure connected to Web2 and Web3. To achieve this vision, we are extending the key Web payment criteria to the block chain ecology, providing bottom-up support for the emerging autonomous AI Agent economy。

As AI Agent evolves, they move from “processing information” to “involving in economic activity” — proactively paying API, hiring other Agents and buying services. This also raises an entirely new question:

How to audit, pay taxes and regulate when machines are able to spend their own money

Pieverse is addressing this "AI Auditability" on BNB Chain. We launched x402b -- this is a completely new, expanded version of the HTTP payment agreement x402, designed not only for Agent but also for enterprise-level compliance。

it is based on three pillars:

1. Providing original capacity to pay for AI Agent on BNB Chain

2. Auditability and compliance of payments

3. A foundation to pay for the flow of AI Agent

Pillar I: Agent Native Payment Channel

A truly autonomous AI Agent should not rely on manual approval of each transaction, nor should it be restricted for Gas fees. Payment must be embedded in the work environment - HTTP protocol。

the x402 standard initially introduced an elegant concept: original Web3 payment through the HTTP 402 Status Code (Payment Required). But on BNB Chain, its application is limited to a key issue:
The mainstream stabilizers (e.g. USDT, USDC) do not support EIP-3009, i.e. "free of Gas authorized transfers". This means that Agent still has to hold BNB to pay for Gas, thereby destroying the seamless experience。

x402b solves this problem with the pieUSD。

pieUSD is a package stable currency with USDT 1:1, which introduces full EIP-3009 support for BNB Chain to make the real Gas payment free experience。

Motion of work:

• Agent (or user) is authorized to sign off-line

• Facilitator agent submits the transaction and pays on behalf of Gas

• The merchant immediately received the pieUSD。

Results:
AI Agent can now complete the payment directly through a simple Web request without having to hold the Gas token。

PILLAR II: AI COMPLIANCE AND AUDITABILITY

When AI Agent begins to spend its own money, ordinary users, businesses and regulators will inevitably ask:

• What did my Agent buy

• To whom? How much

• PLEASE DISPLAY ALL AI EXPENSE VOUCHERS AND INVOICES。

THIS IS THE “AI AUDITABILITY ISSUE”。
Traditional block chain payments can only show transactions without generating compliance receipts or retroactive bills。

x402b Introduction of the Compliance Layer layer through Pieverse Facilitator。

It automatically generates electronic receipts that meet the requirements of the Bailiwick at each payment settlement and keeps them permanently on BNB Greenfield。

Core characteristics:

• Automatic compliance: supporting United States, EU, Asia-Pacific format standards

• Protection against tampering: receipt chained storage to meet long-term audit (e.g. 5 years)

• Protection of privacy: Supports dissensitization and selective disclosure of tax numbers。

Results:
each transaction x 402b brings its own certified invoice and compliance book, which achieves “default by default”。
Enterprises can be assured that AI Agent is deployed and that all expenditures are automatically recorded, audited and retroactive。

Pillar III: The future of Agent Flows

The first Agent payments will be based on a single transaction: an API call, corresponding to a payment。
BUT WITH THE INCREASED COMPLEXITY OF AI, THE REAL FUTURE WILL BE PAYMENT AND DYNAMIC TASK SETTLEMENT。

Enterprises are no longer willing to pay in advance for the lump sum, but prefer to pay on the basis of usage (Pay-as-you-go), such as cloud computing。

x402b is the cornerstone of the future sustainability framework。
The subsequent version will support streaming payments so that Agent can:

• Employment of other Agents in minutes

• Token to pay for the transfer of large models

• Real-time billing and mandate interruptions achieved。

This makes payments safer, more flexible, and helps the birth of the A2A Economy。

Operational mechanisms

x402b maintains full compatibility with the original x402 by extending compliance and storage layers only on BNB Chain。

Brief description of the process:

1. CLIENT → RESOURCE SERVER: SEND HTTP REQUESTS WITH X-PAYMENT HEADERS

2. Resource server → Facilitator: validate signature, initiate settlement

3. Facilitator block chain: call pieUSDtransferWithAuthorization(c) Acquire Gas transfers

4. Facilitator BNB Greenfield: Generate and upload receipts (optional)

5. Returns a standard response with a receipt link。

Summarizing the sentence: User Signature, Facilitator Submitted, Greenfield Certificate. One request, closing the payment and compliance loop。

Core values: move BNB Chain from payment networks to enterprise-level infrastructure

x402b Upgrade BNB Chain from “payable” to “compatible, auditable, sustainable” payment base。

Core values:

1. Enterprise-level integration: original support receipts, invoices and tax compliance

2. Greenfield Site: demonstrates its real value in the storage of financial and regulatory data

3. Enterprise Ready: no Gas, auditable, standardized。

Conclusion: Build a trusted Agent economic bottom

x402b is not only a payment agreement, but also a trust infrastructure for the AI Agent economy。
It fully answered the opening question:

How to audit, tax and regulate when machines spend money

through its three pillars, x 402b was achieved:

• Auto-capacity to pay: PieUSD free of Gas payments to make Agent truly independent。

• Auditable compliance: Auto-generated anti-false altered invoices and bills, permanently stored on the chain。

• Sustained payment framework: sets the technology floor for the future Agent-to-Agent economy。

x402b makes BNB Chain the first enterprise-level default compliance payment infrastructure。
This means that the enterprise can secure the deployment of AI Agent and that all expenditures are automatically recorded, traceable and auditable。

And for ecology, x 402b will open up a whole new era -- a transparent, credible, smart-pay-driven, decentralised Agent economy。