AI Agents Query Enterprise Data Autonomously
Access vetted datasets via x402 protocol with automatic USDC micropayments—no subscriptions, no rate limits, no API keys.
Your wallet is your identity. Query PostgreSQL databases from multiple providers with cryptographic payment verification.
How It Works
Three simple steps to autonomous data access
Set Up Wallet
Install MetaMask or any Web3 wallet, connect to Base network, and fund with USDC for query payments—no account registration required.
Discover Providers
Browse the marketplace to find vetted data providers, view their pricing models, and get provider IDs for queries.
Query via x402
Send SQL queries to the x402 gateway, sign payment authorizations with your wallet, and receive data with automatic USDC settlement.
Per Agent Action Payment Flow
Autonomous payments for every query with cryptographic verification
Send Query Without Payment
POST your SQL query to the x402 gateway with your wallet address and provider ID:
-H "Content-Type: application/json" \
-d '{
"sql": "SELECT * FROM vault_metrics WHERE symbol='YFI'",
"agentWallet": "0xYourWalletAddress",
"providerId": "550e8400-e29b-41d4-a716-446655440000"
}'
Receive Payment Requirements
Gateway responds with HTTP 402 and PaymentRequirements showing the exact cost:
"x402Version": 1,
"accepts": [{
"scheme": "exact",
"network": "base-mainnet",
"maxAmountRequired": "25000", // 0.025 USDC
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"payTo": "0xProviderWallet",
"extra": {
"paymentRequestId": "b2f3d3c7-...",
"estimatedCost": "0.025000"
}
}]
}
Sign Payment Authorization
Use your wallet to sign an EIP-3009 transferWithAuthorization payload:
domain: { name: "USD Coin", version: "2", ... },
types: { TransferWithAuthorization: [...] },
value: {
from: wallet.address,
to: paymentRequirement.payTo,
value: paymentRequirement.maxAmountRequired,
validAfter: 0,
validBefore: Math.floor(Date.now() / 1000) + 300,
nonce: generateNonce()
}
});
Retry with X-PAYMENT Header
Resend the same query with the signed authorization in the X-PAYMENT header:
-H "Content-Type: application/json" \
-H "X-PAYMENT: eyJ4NDAyVmVyc2lvbiI6MSwi..." \
-d '{ same payload }'
"rows": [...],
"rowCount": 42,
"actualCost": "0.024500",
"paymentSource": "x402",
"settlement": {
"transaction": "0xabc...",
"network": "base-mainnet"
}
}
Payment settlement happens automatically on Base network. Your USDC is transferred only after the query succeeds.
Getting Started
Set up your agent for autonomous data access
Set Up Your Wallet
Install a Web3 wallet (MetaMask, Coinbase Wallet, or any EIP-3009 compatible wallet):
- Add Base network (Chain ID: 8453, RPC: https://mainnet.base.org)
- Fund your wallet with USDC on Base (contract: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)
- Your wallet address (0x...) is your agent identity—no account registration needed
Implement x402 Payment Flow
Integrate the x402 protocol into your agent (see flow above). Key considerations:
- Use ethers.js or viem for EIP-3009 signature generation
- Generate unique nonces (recommended: keccak256 of timestamp + random bytes)
- Handle failed queries gracefully—credits apply automatically to next request
- Respect rate limits: 50 queries per 15 minutes per IP
Start Querying
Send your first query and verify the payment settlement on Base network:
- Verify transaction on BaseScan using the hash from settlement response
- Check the X-PAYMENT-RESPONSE header for settlement metadata
- Monitor your credit balance at GET /api/balance/:wallet/:providerId
Need help? Check out our documentation or join our Discord community.
Why AI Agents Choose x402
Wallet-Based Identity
Your Ethereum address is your identity. No API keys, no passwords, no traditional authentication—just cryptographic signatures.
Autonomous Payments
Sign EIP-3009 payment authorizations with your wallet. Automatic USDC settlement on Base network for every successful query.
PostgreSQL-Native
Standard SQL queries via HTTP. No proprietary APIs—use the same queries you'd run against any PostgreSQL database.
Failed-Query Credits
Automatic refunds when queries fail. Credits apply to future queries, reducing payment requirements or eliminating them entirely.
Complete Feature Set
Transparent Per-Query Pricing
Pay only for queries you make. No subscriptions, no hidden fees, no surprise charges.
How Pricing Works
Provider-Set Pricing
Each data provider configures their own pricing model. You see the exact cost before signing payment authorization.
Cost Estimation
Gateway runs PostgreSQL EXPLAIN on your query to estimate cost. The 402 response shows maxAmountRequired upfront.
Platform Revenue Share
70% to data provider, 30% to platform. Split happens automatically during settlement—you only sign one payment.
Failed-Query Refunds
If your query fails after payment, you receive automatic credit. Credits reduce or eliminate future payment requirements.
Common Pricing Models
Row-Based
Cost per 1,000 rows returned (e.g., $0.001 per 1K rows)
Example: SELECT returning 5,000 rows = $0.005
Complexity-Based
Based on PostgreSQL query plan cost (EXPLAIN output)
Example: Complex JOIN with cost 1,000 = $0.01
Data Transfer
Cost per MB of data returned in response
Example: 10 MB response = $0.05
Time-Based
Cost per millisecond of query execution time
Example: 500ms execution = $0.02
No Subscription Fees
Unlike traditional APIs, there are no monthly subscriptions, no API tiers, and no per-seat licenses.
Pay only for the data you query. USDC payments on Base network mean low transaction fees (~$0.01) and instant settlement.
Real-World Use Case
AI Agent Accessing DeFi Data
Yearn Finance · Real-time Vault Metrics
An AI agent needs real-time Yearn Finance vault metrics updated every 15 minutes. Using SerenDB x402, the agent discovers Yearn's data provider in the marketplace and queries autonomously with automatic USDC payments.
Agent Workflow:
- Queries:
SELECT * FROM vault_metrics WHERE updated_at > NOW() - INTERVAL '15 minutes' - Receives 402 response with estimated cost: $0.025 USDC
- Signs payment authorization with wallet (no human intervention)
- Receives fresh data in <1s with transaction hash on Base network
- Immutable audit trail: query + payment recorded on blockchain
Ready to Build Autonomous Agents?
Set up your wallet and start querying enterprise data with automatic USDC payments