CRA Factory — build your own paying agent

What do you want to build?

Two sides of the same rail. One gives your AI a budget to buy with. The other puts a price on an API you already run.

1. Where will the agent live?

The program you talk to your AI in. The agent plugs into it as a set of tools.

2. How much may it spend?

Pick a starting point, then change any number. These are hard limits: the AI cannot raise them, because it never sees them as something it can edit.

Per day, in total ($)The most it can spend in 24 hours, whatever happens. Per seller, per day ($)So one site cannot take the whole budget. Per payment ($)The most a single call may cost. Most calls cost a fraction of a cent. Payments per minuteA brake, in case the AI gets stuck in a loop.

3. Which sites may it pay?

Leave empty to let it pay any site that asks over x402, within the limits above. Or list the only sites you trust, one per line.

Allowed sites (optional)

4. Network and key file

The agent gets its own new wallet. Its key is created on your machine by the command below, never by this page. Leave the path as it is unless you want the file somewhere else.

Key file, full pathLeft as it is, the command uses the .cra-agent folder in your home. Change it only if you want another place, with the full path.

5. Where is your USDC now?

The agent pays on Arc. If your dollars are on Base or Solana, one command brings them over through Circle's CCTP and puts them where payments are made from. You run it, not the AI.

Your agent, in words

1. Your API and your wallet

The API stays where it is and as it is. Buyers will call a small server that stands in front of it, and pay you on Arc.

Address of your APIWhere your API answers today. It can be private, on localhost, as long as the command runs on the same machine. Wallet that gets paidAn address you control on Arc. Only the address: never a key. Solana address (optional)Most x402 buyers today are on Solana. With this, the same routes are also for sale to them, and they pay you in USDC on Solana, on this address. Nothing crosses chains. Lightning connection file (optional)To be paid in sats as well, on your own Lightning node. Write the path, on the machine that runs the command, of a file that holds a receive-only Nostr Wallet Connect string from your node, like /home/you/.secrets/nwc-receive. Only the path: never the connection itself. Let the CRA facilitator check the Lightning paymentsA Lightning payment is checked once and its proof remembered, so it cannot be used twice. By default the command keeps that record in a file on your machine. With this, our facilitator keeps it instead: open to anyone, no registration, nothing to pay. Pick one and keep it.

2. The price

Per call, in dollars. Agents buy small things often: a fraction of a cent to a few cents is the usual range. You can price single paths differently later, with the --route option.

Price per call ($) Name buyers see (optional)

Charge what each call costsFor calls that cost a cent one time and a dime the next. The price above becomes the most a call can cost; the buyer signs once for it, and your API says what each call did cost in an X-Charge-USD header. Only that is taken. On Arc, settled by our facilitator: Solana and Lightning sell set prices. Let browser wallets pay tooAgents pay through Circle Gateway. People with a wallet in the browser need our facilitator, which settles for your wallet and pays the gas, up to a daily allowance. It needs one signature from the wallet that gets paid: the steps below will send you to sign it. Paths that stay free (optional)One per line. Health checks, documentation, anything you do not want to charge for.

3. Network and public address

If you already know the https address buyers will use, write it and the command lists you on the market by itself. If not, leave it empty and add it later from the market page.

Public https address (optional)

Your shop, in words

What this page does not do

It does not create a wallet, see a key, or send anything anywhere: everything above is put together in your browser, and the key is made on your machine by the command you paste. The command is open source: the “by hand” section shows every step it takes. It does not hold your money either. The agent spends from its own small wallet, which you fill, and it can never spend more than what is in it or more than the limits you set.

Want to see a payment first, with no install? Buy one API call from your browser wallet. Every payment made through us is listed on the status page.

Build your own paying agent