Install
openclaw skills install a2a-paymentsA2A Payments
Blockchain USDC payments via APay — pay services, manage budgets, open streaming channels, and handle x402 protocol.
A2A Payments (APay)
Blockchain-native USDC payments for AI agents on Base chain. Pay for services, manage budgets, and handle micropayments.
Quick Start
Check your balance:
Use apay_check_balance to see my USDC balance
Pay a service:
Use apay_pay_service with serviceId "svc-123" and amount "0.50"
Available Tools
Balance & Budget
| Tool | Description |
|---|---|
apay_check_balance | Check USDC balance, daily budget, spending limits |
apay_budget_check | Verify if a specific amount is affordable |
apay_spending_history | Get spending analytics and history |
Payments
| Tool | Description |
|---|---|
apay_pay_service | Pay a service (agent pays gas) |
apay_pay_signed | Gasless signed payment (server submits on-chain) |
apay_estimate_cost | Estimate cost including 0.5% platform fee |
Services
| Tool | Description |
|---|---|
apay_list_services | List available APay services |
apay_get_service | Get detailed service info |
Payment Channels (Streaming)
| Tool | Description |
|---|---|
apay_channel_status | Check channel status |
apay_stream_open | Open channel with USDC deposit |
apay_stream_pay | Sign off-chain micropayment |
apay_stream_close | Close channel (refund unspent) |
x402 Protocol
| Tool | Description |
|---|---|
apay_x402_fetch | Fetch URL with automatic x402 payment on HTTP 402 |
Workflows
Pay for a tool execution
apay_budget_check— verify affordabilityapay_estimate_cost— see total with feesapay_pay_service— execute payment- Receive payment receipt with tx hash
Streaming micropayments
For services that charge per-request (API calls, data feeds):
apay_stream_open— deposit USDC into channelapay_stream_pay— sign micropayments (off-chain, instant)apay_stream_close— settle on-chain, refund remainder
x402 auto-payment
For services using the HTTP 402 payment protocol:
Use apay_x402_fetch with url "https://api.example.com/premium/data" and maxPayment "1.00"
The tool automatically detects 402 responses, pays the required amount, and retries the request.
Network
- Chain: Base (Coinbase L2)
- Stablecoin: USDC (6 decimals)
- Model: Escrow-based sessions with spending limits
- Testnet: base-sepolia for development