Payment infrastructure for the autonomous economy
On-chain USDC vaults with policy-controlled AI agent access. Machine-to-machine payments made safe, auditable, and instant.
Manifesto
The future of billing is autonomous
Billing is broken for machines
APIs still rely on human-era billing — monthly invoices, credit card forms, manual approvals. When an AI agent needs to buy compute, fetch data, or pay for a service, it shouldn't wait for a human to enter card details. Machines need per-action, per-second payment rails built for their speed.
AI agents are economic actors
We're entering an era where autonomous agents procure resources, negotiate prices, and transact on behalf of humans. They need real payment capability — not simulated tokens or playground credits, but actual value transfer with actual guardrails.
Policy-controlled autonomy
Freedom within bounds. Vault owners set budgets, category restrictions, velocity limits, and approval thresholds. Agents operate freely within those constraints. When a transaction exceeds policy, it's escalated — not blocked forever, not approved blindly.
On-chain settlement, off-chain intelligence
Smart contracts on Solana and Base handle custody and settlement — your keys, your funds. The policy engine and API run off-chain for speed and flexibility. The result: sub-second decisions with on-chain finality.
How it works
Three steps to autonomous payments
Fund a Vault
Deposit USDC into a non-custodial on-chain vault. You keep your keys. Your funds stay in a smart contract only you control.
Authorize Agents
Register AI agents and attach spending policies — budgets, categories, merchants, time windows, approval rules. Define the boundaries.
Agents Transact
Agents request payments. The policy engine evaluates in real-time: auto-approve, escalate for human approval, or reject. Settlement happens on-chain.
Features
Everything agents need to transact
Policy Engine
Budget limits, category controls, velocity caps, time restrictions, and multi-level approval rules. Six configurable check layers.
Escrow Payments
Conditional holds with time-release, oracle confirmation, delivery verification, and dispute resolution. Trustless commerce.
Multi-Chain
Solana for speed, Base L2 for EVM compatibility. Identical Vault, Registry, and Escrow contracts on both chains.
Webhooks
Real-time notifications for 11 event types. HMAC-SHA256 signatures. Automatic retries with exponential backoff.
SDK Ecosystem
TypeScript and Python SDKs. LangChain integration for AI agent frameworks. Merchant SDK for payment receivers.
Emergency Controls
Instant vault freeze, agent revocation, real-time spending visibility. Your kill switch, always one click away.
Developer experience
A few lines of code
Integrate autonomous payments into any AI agent framework.
import Subcent from "@subcent/sdk";
const subcent = new Subcent({
apiKey: "sc_live_...",
network: "mainnet",
});
// Create a vault
const vault = await subcent.vaults.create({
owner_wallet: "0x...",
chain: "base",
});
// Register an agent with a spending policy
const agent = await subcent.agents.create({
vault_id: vault.vault_id,
label: "shopping-agent",
});
// Agent requests a payment
const payment = await subcent.payments.request({
agent_id: agent.agent_id,
merchant_id: "merchant_abc",
amount: "12.50",
currency: "USDC",
category: "groceries",
});
console.log(payment.status);
// "completed" | "pending_approval" | "rejected"Ready to build?
Start integrating autonomous payments in minutes. Read the docs, explore the SDK, or dive into the source.