Generate a Brazilian Pix BR Code ("Copia e Cola") plus QR PNG from a Pix key. JSON body: key, merchant_name required; amount, merchant_city, txid, description optional. Returns brcode and qr_png_base64.
| Network | Scheme | Amount | Pay To |
|---|---|---|---|
| Base | exact | $0.01 USDC | 0x8799...f527 |