Quickstart

From a new account to a paid test request in about ten minutes, on a free test network.

1. Create a site. In the dashboard, add a site with your domain and the wallet address that should receive payments.
2. Start in test mode. Under tokens, select Base Sepolia EURC (or USDC). A site with only test tokens is in test mode: settlements are free and need no credits.
3. Set a price. Add a price rule, for example /premium/** at 0.01. Paths without a rule use the site's default price; set it to 0 to keep them free.
4. Create an API key. On the site page, create a key and copy it together with the site ID. The key is shown once.
5. Connect your server. Install the integration for your stack:

npm install @pennipay/x402

pip install flask requests   # then copy the example from docs/python

# no package: copy penni.php from docs/php and require it

# no package: copy the Penni middleware from docs/go (standard library only)

# Plugins → Add New → Upload Plugin → penni.zip, then Settings → Penni

Then set the two values as environment variables on your server:

PENNI_SITE_ID=site_...
PENNI_API_KEY=x402_sk_...

Check it

Request a priced path without paying. You get a 402 with a PAYMENT-REQUIRED header that holds the price:

curl -si https://your-site.example/premium/report | grep -i -E '^HTTP|^payment-required'

Now pay it. On the site page in the dashboard, press Pay with test tokens to pay the path from a browser wallet (MetaMask, Phantom, Lace) exactly as an agent would. Test EURC and USDC come free from Circle's faucet. The paid request returns 200 with a PAYMENT-RESPONSE header, and the payment shows up on the Test tab of the site's analytics.