Four-Party Payment Model
ItPay Protocol introduces a four-party payment model that fundamentally separates information routing from funds settlement. This is the core architectural innovation that enables AI-native payments without requiring ItPay to become a regulated financial institution.
The Four Parties
┌─────────────────────────────────────────────────────────────────────────┐
│ FOUR-PARTY MODEL │
│ │
│ │
│ ╔═══════════════════════╗ ╔═══════════════════════╗ │
│ ║ ║ ║ ║ │
│ ║ ① HUMAN (Payer) ║ ║ ② AGENT / MERCHANT ║ │
│ ║ ║ ║ (Payee) ║ │
│ ║ • The end user ║ ║ ║ │
│ ║ who pays ║ ║ • AI agent or ║ │
│ ║ • Has a real-world ║ ║ merchant selling ║ │
│ ║ wallet (bank, ║ ║ a service ║ │
│ ║ e-wallet, crypto) ║ ║ • Receives funds ║ │
│ ║ ║ ║ via their channel ║ │
│ ╚═══════════════════════╝ ╚═══════════════════════╝ │
│ │ ▲ │
│ │ ① Pays via channel │ │
│ │ (WeChat, PromptPay, etc.) │ ④ Funds arrive at │
│ ▼ │ merchant's account │
│ ╔═══════════════════════╗ ╔═══════════════════════╗ │
│ ║ ║ ║ ║ │
│ ║ ③ CHANNEL ║ ║ ④ ItPay Platform ║ │
│ ║ ║ ║ ║ │
│ ║ • WeChat Pay ║ ──── ║ • Information ║ │
│ ║ • Alipay ║ Info ║ routing ONLY ║ │
│ ║ • PromptPay ║ Path ║ • Does NOT touch ║ │
│ ║ • QRIS ║ ║ money ║ │
│ ║ • Bank Transfer ║ ║ • Provides protocol ║ │
│ ║ • Crypto stablecoin ║ ║ & channel infra ║ │
│ ║ • etc. ║ ║ • Routes payment ║ │
│ ║ ║ ║ instructions ║ │
│ ╚═══════════════════════╝ ╚═══════════════════════╝ │
│ │
│ ←──────────── Funds Flow (channel-to-channel) ────────────→ │
│ ←──── Information Flow (via ItPay Platform) ──────────→ │
└─────────────────────────────────────────────────────────────────────────┘
① Human (Payer)
The end user who wants to purchase a service from an AI agent or merchant. The human:
- Holds a real-world wallet: bank account, e-wallet (WeChat, Alipay), or crypto wallet
- Initiates payment through their preferred channel
- Owns the transaction — all consent and authorization happens at the channel level
- Never needs to hold tokens, create accounts, or pre-fund an ItPay wallet
② Agent / Merchant (Payee)
The AI agent or merchant providing a service (e.g., a chatbot, a data analytics agent, a subscription service). The payee:
- Publishes a service manifest describing what they offer and how much it costs
- Receives funds directly into their own channel wallet or bank account
- Does not need to integrate with every payment channel — ItPay handles channel routing
- Can be an AI agent with no human operator
③ Channel
The payment network that actually moves money. Channels are real-world, regulated payment systems:
- WeChat Pay — China's dominant mobile wallet
- Alipay — Alibaba's payment ecosystem
- PromptPay — Thailand's real-time payment system
- QRIS — Indonesia's QR payment standard
- Bank Transfer — Traditional bank rails (SEPA, ACH, SWIFT)
- Crypto Stablecoins — USDC, USDT on L2 networks
Channels handle KYC/AML, fund custody, dispute resolution, and settlement. ItPay does not replicate any of these regulated functions.
④ ItPay Platform (Information Router)
ItPay never touches money. The platform:
- Routes payment information between the payer, payee, and the appropriate channel
- Generates channel-specific payment instructions (QR codes, deep links, redirect URLs)
- Tracks payment intent state (created → authorized → captured → settled)
- Provides reconciliation data so both parties can match ItPay records against channel statements
- Enables FX conversion quotes (but settlement happens at the channel level)
The Core Principle
ItPay does NOT touch money.
This principle is non-negotiable. ItPay avoids the regulatory burden of being a money transmitter, payment processor, or financial institution. Every aspect of the architecture enforces this boundary:
- ItPay has no custody of funds — no wallet, no balance, no escrow
- All settlements are channel-to-channel (payer's channel → payee's channel)
- ItPay only generates payment instructions and reconciles results
- Channel adapters are stateless — they produce payloads, not hold funds
- The platform operates on an information-only basis: intent creation, routing, reconciliation
JSON Example: Payment Through the Four-Party Model
Here is what a complete payment looks like from the perspective of each party:
{
"payment_id": "pay_2xK3m9QrL8vN5pW1",
"intent": {
"amount": {
"value": "25.00",
"currency": "USD"
},
"description": "Monthly subscription - Premium Analytics Agent",
"payee_service": "agent:analytics-pro@itpay.network"
},
"parties": {
"payer": {
"role": "human",
"identifier": "user@example.com",
"channel_account": "wechat://user/openid_abc123"
},
"payee": {
"role": "agent",
"identifier": "agent:analytics-pro@itpay.network",
"channel_account": "promptpay://merchant/merchant_id_xyz789"
},
"channel": {
"name": "wechat_pay",
"type": "e_wallet",
"jurisdiction": "CN",
"settlement": {
"from": "wechat://user/openid_abc123",
"to": "alipay://merchant/merchant_id_xyz789",
"fx_conversion": {
"from": "USD",
"to": "CNY",
"rate": "7.24",
"provider": "fx_service",
"locked_at": "2026-05-27T10:00:00Z"
}
}
},
"platform": {
"role": "information_router",
"id": "itpay-platform-v1",
"actions": [
"generated_qr_code",
"routed_to_wechat",
"notified_payee",
"recorded_reconciliation_data"
],
"does_not": [
"hold_funds",
"maintain_balance",
"perform_kyc",
"settle_transaction"
]
}
},
"flow": {
"steps": [
{
"step": 1,
"actor": "human",
"action": "scans_wechat_qr_code",
"detail": "ItPay generates a WeChat Pay QR code showing the USD-equivalent CNY amount"
},
{
"step": 2,
"actor": "channel",
"action": "authorizes_payment",
"detail": "WeChat Pay debits CNY 181.00 from the payer's WeChat wallet"
},
{
"step": 3,
"actor": "platform",
"action": "receives_channel_callback",
"detail": "WeChat Pay notifies ItPay that payment is authorized; ItPay updates payment intent to 'captured'"
},
{
"step": 4,
"actor": "platform",
"action": "notifies_payee",
"detail": "ItPay sends webhook to the analytics agent: payment captured, deliver service"
},
{
"step": 5,
"actor": "channel",
"action": "settles_funds",
"detail": "WeChat Pay settles funds (minus fees) to the payee's PromptPay account via cross-border settlement"
},
{
"step": 6,
"actor": "platform",
"action": "generates_reconciliation",
"detail": "ItPay creates reconciliation record matching the payment intent to channel settlement file"
}
]
}
}
Comparison: Traditional Three-Party vs. ItPay Four-Party Model
| Aspect | Traditional Three-Party | ItPay Four-Party |
|---|---|---|
| Parties | Payer, Merchant, Channel (3) | Human, Agent/Merchant, Channel, ItPay Platform (4) |
| Platform role | Processes funds (payment processor) | Routes information only |
| Funds custody | Platform holds/processes funds | Platform never touches funds |
| Regulatory burden | High (MSB/payment processor licenses) | Low (protocol/information routing) |
| Settlement | Platform → Merchant (net settlement) | Channel → Merchant (direct settlement) |
| Channel integration | One channel per integration | Unified adapter per channel, plugged into protocol |
| AI-native features | None — designed for web/mobile | QR AI recognition, agent discovery, agent-to-agent negotiation, MCP integration |
| Reconciliation | Platform provides settlement report | Matches platform intent ↔ channel statement |
| ID system | Merchant account on platform | Agent identity via agent IDs, channel accounts are separate |
| Payment intent model | Simple (charge/capture/refund) | Rich: one-time, cumulative, subscribe, budget-enforced |
| Multi-channel | Rare — merchants pick one processor | Built-in — channel is a runtime decision, not integration-time |
Why This Model Matters for AI
Traditional payment models assume a human buyer interacting with a web/mobile interface. AI agents change the equation:
- Agent-to-Agent payments — Two AI agents negotiate a payment without human intervention for every transaction
- Micro-payments — Agents may make hundreds of tiny payments per hour; escrow/hold models don't scale
- Multi-currency — Agents operate across borders by default; payment channels must follow
- No pre-funding — Agents should not need to pre-load wallets; the human's existing channel account suffices
- Channel diversity — Different humans prefer different payment methods; the agent should accept any
The four-party model absorbs all of these requirements without requiring ItPay to become a regulated financial entity.
Related
- Architecture Overview — The services that implement this model
- Two-Layer Design — Open Protocol vs. Paid PaaS
- Payment Intent — The data model for payment orchestration