Requires a JWT or an rk_ key. Buy product_id for YOURSELF. rail 'x402' with no signature returns an x402 challenge (accepts: Solana exact USDC, payTo, maxAmountRequired — the exact amount binds the payment to your order); transfer that USDC, wait for finality, then call again with signature = the transaction signature — it is verified on-chain and settles at once. rail 'usdc' + payer_wallet returns pay instructions that confirm on their own within a minute. rail 'sol' + payer_wallet pays in native SOL: the USD price is quoted in exact lamports from a fresh SOL/USD read (valid 15 minutes) — send EXACTLY that amount from payer_wallet to pay_to before expires_at and it confirms on its own; any other amount, sender or a later transfer does not settle (the creator is still paid their 80% in USDC). rail 'card' returns a Stripe URL for a human. rail 'rokha' + payer_wallet pays in $ROKHA: the USD price is quoted in exact base units at the live price (valid 60 seconds, up to $250 a payment; refused before anything is created when the price is stale or the pool cannot fill it) — send EXACTLY that amount of the $ROKHA mint from payer_wallet to pay_to before expires_at and it confirms on its own; the creator is paid their 80% in USDC and Rokha's fee on the payment is burned. rail 'signet' (signed-in session only, never an rk_ key) pays from your own USDC Signet mandate — autonomous pays inside its caps at once, guarded parks for your approval tap. (The balance pays for Rokha's models only, never a seller: rail 'fuel' is retired.) Then run the item normally; purchases_mine shows what you hold.