This tutorial walks a realistic use case: a landlord owes a security deposit, and you want proof of delivery that would hold up if you later pursue it.
1. Price it certified with e-Return Receipt
For something you may later show a judge, use certified_err ($14.99) — it gives a signature, date, and tracking record.
The response includes the all-in price and a confirmation_token.
2. Create the order
Save the order.id and the capability.cancel_token.
3. Send the payment link to the human
order.payment_url — the landlord-aggrieved party pays, then it’s screened and mailed automatically.
4. Track with webhooks (or polling)
Prefer a webhook so you’re pushed the outcome:
Verify incoming events with X-paperplane-Signature (see Webhooks).
5. Keep the receipt
On delivered, the tracking number + e-Return Receipt record is your proof. The webhook event includes tracking_number and event_url.
Done
You mailed a certified, court-ready demand letter from code in under a minute, with delivery proof wired into your own system. Last modified on September 17, 2026
