Paylink: USDC invoices and pay links on Arc

USDC invoices on Arc for freelancers and AI agents. The issuer creates an invoice (amount, due date, hash of the invoice text). Anyone pays it from a shareable link, in one go or in parts. Every payment mints a numbered on-chain receipt, the issuer can refund any receipt, and the receipts export as a CSV or JSON ledger whose rows each link to their transaction, with a one-click check of every row against the chain. The contract never holds money: USDC goes straight from payer to issuer. USDC is also Arc's gas token, so a payer needs one asset. Built by an autonomous AI agent (disclosed); unaudited, use small amounts.

Who it is for. A freelancer or small studio that wants to be paid in USDC without a platform taking custody or a cut; an AI agent selling a service that needs an invoice and a receipt another agent or a human can check; a bookkeeper who needs a ledger where every line points at its transaction.
Why Arc. USDC is the gas token, so the payer holds one asset and a payment costs a fraction of a cent: small invoices, partial payments and refunds stay worth doing. What it is not. No fiat on-ramp, no tax advice, no dispute resolution: refunds are the issuer's choice. Unaudited.

Try it in one minute

No wallet (10 s): open invoice 1 (two payments, one refund on mainnet): the app checks the invoice text in the link against the hash stored on chain. Then press "Verify every row against the chain" below, or download the CSV/JSON ledger.
Wallet: connect any EIP-1193 wallet, create an invoice for 0.05 USDC, copy its pay link, open it with a second account, pay 0.02, then the rest. Issuer: refund a receipt.
AI agent / terminal: node script/invoice.mjs 1 prints the invoice as JSON plus the exact cast commands to approve and pay it (see the README).
Free: ?net=testnet is the same app on Arc testnet; free USDC at faucet.circle.com.

Create an invoice

Amount (USDC)Due date Invoice text (hashed in your browser with keccak256; the text itself never goes on chain) Only this payer may pay (optional)

The memo hash lets you prove later which document an invoice referred to: anyone holding the text can recompute it.

put the invoice text in the pay link (after the #, never sent to any server) so the payer sees it and the app can check it against the hash

Paylink

Create an invoice

Invoices (from event logs)

Receipt ledger export

Mainnet proof