Table of Contents
A Circle Agent Nanopayment is a gas-free USDC payment from an AI agent wallet down to $0.000001, settled through Gateway batched settlement against an x402 service.
Deposit USDC into a Gateway balance once onchain. Then the agent signs EIP-3009 TransferWithAuthorization offchain, Gateway batches and settles, and the seller withdraws. Same-chain x402 is free of the Gateway protocol fee. Crosschain x402 pays 0.5 bps.
This guide walks the Circle CLI path: deposit, discover, pay, and check balance. For wallet setup first, see how to set up an AI agent wallet. For the sell side, see how to accept x402 USDC payments from AI agents.
Key Takeaways
- Install Circle CLI (npm install -g @circle-fin/cli) after the Agent Wallets quickstart.
- Deposit USDC into the Gateway Wallet contract once onchain, then spend offchain authorizations.
- Search and inspect x402 services, then pay with circle services pay against your Gateway balance.
- Gas on agent wallets is $0 sponsored (capped, fair use, may change). Gateway protocol fee is 0.5 bps on crosschain x402 and free same-chain.
- Batched settlement makes $0.000001 viable. Individual settle still needs roughly $0.01+ minimum.
What a Circle Agent Nanopayment actually is
Agent Nanopayments sit on Gateway Nanopayments. Circle documents gas-free, batched USDC payments at sub-cent scale for AI agents paying x402-compatible services.
The buyer deposits into a Gateway Wallet contract (one-time onchain). Requests that hit 402 Payment Required get an offchain EIP-3009 authorization. Gateway aggregates authorizations and settles net positions onchain so neither side pays per-payment gas.
Named downside: nanopayments and x402 batch settlement need EOA signatures. They do not support ERC-1271. Smart-contract wallets need a different Gateway path.
Who this is for (and who should skip it)
Use Agent Nanopayments when an AI agent must pay per API call, compute slice, or data fetch in USDC without burning gas on every request.
Skip it when you only need human checkout, a one-shot USDC transfer, or a seller-only middleware install. Those jobs map to ordinary USDC sends or how to accept x402 USDC payments from AI agents.
Circle Agent Marketplace lists 600+ curated x402 services across 15+ networks. Treat that catalog as discovery, not as a compliance guarantee for your own risk policy.
Make checklist (2026)
1. Prerequisites
Install Node.js v20.18.2 or later. Install Circle CLI.
npm install -g @circle-fin/cli
Complete the Agent Wallets quickstart so auth and a funded wallet already exist. See how to set up an AI agent wallet.
2. Deposit USDC into Gateway
Deposit from your wallet on Base (Circle quickstart example uses 5 USDC).
circle gateway deposit --amount 5 --address 0xYourWalletAddress --chain BASE --method direct
That deposit is the one-time onchain step into the Gateway Wallet contract. Later pays are offchain authorizations against that balance.
3. Discover an x402 service
Search the Agent Marketplace, then inspect payment requirements before you pay. Example: circle services search "weather" then circle services inspect <url>.
Pick services whose asset, network, amount, and payTo match a chain and balance you already hold.
4. Pay with Circle CLI
Pay against your Gateway balance on Base. The CLI prints the service response body.
circle services pay <url> --address 0xYourWalletAddress --chain BASE --max-amount 0.01
Settlement hits your Gateway balance, not a fresh wallet gas burn per call.
5. Check balance and withdraw later
Confirm remaining Gateway balance, then withdraw back to the wallet when the agent is done.
circle gateway balance --address 0xYourWalletAddress --chain BASE
Keep spend limits and recon in your own ops stack. See how to reconcile AI agent USDC spend.
Fees that matter (as of September 2026)
| Fee | Amount (Circle docs) | When it applies |
|---|---|---|
| Gas | $0 (sponsored) | Agent wallet onchain txs (capped, fair use, may change) |
| Gateway protocol fee | 0.5 bps | Crosschain x402 payments (free same-chain) |
| Eco deposit fee | Set by Eco | Gasless Gateway deposits via Eco (third-party) |
| Batched nanopayment floor | Down to $0.000001 | With Gateway batched settlement |
| Individual settle floor | About $0.01+ | Without batching |
Primary sources: Agent Nanopayments, nanopayments quickstart, agent wallet fees.
How this differs from a plain x402 facilitator pay
An x402 facilitator can verify and settle a payment authorization without you running Gateway yourself. Agent Nanopayments put the buy-side balance inside Gateway and use Circle CLI for deposit, search, and pay.
If you are choosing who settles seller receipts, read how to choose an x402 facilitator for USDC. If you are pricing an API you sell, read how to price an x402 API in USDC.
Operational pitfalls
Skipping the Agent Wallets quickstart. CLI pay fails without auth and a funded wallet.
Crosschain fee surprise. Same-chain Gateway protocol fee is free. Crosschain x402 adds 0.5 bps.
Eco deposits without a review. Eco is a third-party fast-deposit path Circle does not operate or audit.
Treating Marketplace listing as risk approval. Sanctions screening on seller payout wallets is not your full vendor diligence.
Ignoring the EOA requirement. Batch settlement needs EOA signatures. Do not assume an ERC-1271 smart wallet will work on this path.
Related playbooks
Wallet bootstrap: how to set up an AI agent wallet.
Sell-side accept path: how to accept x402 USDC payments from AI agents.
Facilitator choice: how to choose an x402 facilitator for USDC.
Pricing the API you sell: how to price an x402 API in USDC.
Spend recon: how to reconcile AI agent USDC spend.
FAQ
How do I make a Circle Agent Nanopayment in USDC?
Install Circle CLI, finish the Agent Wallets quickstart, deposit USDC into Gateway, then pay an x402 URL with max-amount set.
What is the minimum Circle Agent Nanopayment amount?
Circle documents gas-free USDC nanopayments down to $0.000001 with Gateway batched settlement. Individual settle without batching still needs roughly $0.01+.
When should I use same-chain vs crosschain Gateway for agent pays?
Prefer same-chain when the service and your Gateway balance share a network, because the Gateway protocol fee is free. Use crosschain only when liquidity forces it, and budget 0.5 bps.
Why do Agent Nanopayments need a Gateway deposit first?
The deposit funds the Gateway Wallet contract once onchain. Later pays are offchain EIP-3009 authorizations that Gateway batches, which is what removes per-payment gas.
Should I use Eco for Gateway deposits?
Only after you read Eco own docs and test the flow. Circle states Eco is a third-party service it does not operate or audit, and Eco sets its own deposit fee.
What is the downside of Circle Agent Nanopayments?
You inherit Gateway batch rules, EOA-only signatures, sponsored-gas caps that may change, and any Eco or crosschain fee lines. Teams that only need human USDC checkout should skip this stack.
Next step
Fund a Base agent wallet, deposit a small Gateway balance (Circle example uses 5 USDC), pay one Marketplace or inspect-verified x402 URL with a tight max-amount, then confirm Gateway balance before you loop the agent.
This content is provided for informational and educational purposes only and does not constitute financial, investment, legal, or tax advice; no material herein should be interpreted as a recommendation, endorsement, or solicitation to buy or sell any financial instrument, and readers should conduct their own independent research or consult a qualified professional.
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