{ "openapi": "3.1.0", "info": { "title": "XL Pay public payments API", "version": "1.0.0", "description": "Pay a business on XL Pay, or anyone with a crypto domain (.crypto, .nft, .x, .wallet, .bitcoin, .eth and more), in stablecoins or crypto. Built for people and AI agents. XL Pay is non-custodial: every payment goes straight from the payer's wallet to the payee's wallet, and XL Pay never holds funds or keys. Flow: (1) GET who you're paying and which coins they accept, (2) POST action=sale to get the exact address and amount, (3) send exactly that amount from your wallet, (4) POST action=check until status is paid. Amounts are unique per sale, so send the exact amount returned; for XRP also set the destination tag. Agents that speak x402 can instead call /api/x402/pay: one request returns HTTP 402 with USDC payment options, and a retry with a PAYMENT-SIGNATURE header pays and returns the receipt.", "contact": { "name": "Xperience Levels", "email": "info@xperiencelevels.com", "url": "https://xperiencelevels.com/to" } }, "servers": [ { "url": "https://xperiencelevels.com" } ], "paths": { "/api/xlpay/pay": { "get": { "operationId": "lookupPayee", "summary": "Look up who you're paying and which coins they accept", "parameters": [ { "name": "to", "in": "query", "required": true, "schema": { "type": "string" }, "description": "An XL Pay business code (e.g. living-room-wine) or a crypto domain (e.g. xperiencelevels.crypto, name.eth)." }, { "name": "l", "in": "query", "required": false, "schema": { "type": "string" }, "description": "Signed pay-link token from a fixed-price XL Pay link (the l= value in /to/?l=...)." } ], "responses": { "200": { "description": "Payee found", "content": { "application/json": { "schema": { "type": "object", "properties": { "kind": { "type": "string", "enum": [ "business", "domain" ] }, "name": { "type": "string" }, "rails": { "type": "array", "items": { "$ref": "#/components/schemas/Rail" } }, "fixed": { "type": [ "object", "null" ], "properties": { "amount": { "type": "number" }, "note": { "type": "string" } }, "description": "Set when the pay link has a fixed USD price; your amount is ignored." }, "addresses": { "type": [ "object", "null" ], "description": "For crypto domains: the public addresses the domain points to." } } } } } }, "404": { "description": "No business with that code, or the domain has no payment addresses" } } }, "post": { "operationId": "payment", "summary": "Open a payment (action=sale), check it (action=check), or email a receipt (action=receipt, businesses only)", "requestBody": { "required": true, "content": { "application/json": { "schema": { "oneOf": [ { "type": "object", "required": [ "action", "to", "rail", "amount" ], "properties": { "action": { "const": "sale" }, "to": { "type": "string", "description": "Same value as the lookup's to." }, "l": { "type": "string", "description": "Signed pay-link token, if any." }, "rail": { "$ref": "#/components/schemas/RailId" }, "amount": { "type": "number", "minimum": 0.5, "maximum": 25000, "description": "Amount in US dollars. Crypto rails are priced at the live rate and locked for 15 minutes." }, "note": { "type": "string", "maxLength": 80 } } }, { "type": "object", "required": [ "action", "token" ], "properties": { "action": { "const": "check" }, "token": { "type": "string" } } }, { "type": "object", "required": [ "action", "token", "email" ], "properties": { "action": { "const": "receipt" }, "token": { "type": "string" }, "email": { "type": "string", "format": "email" } } } ] } } } }, "responses": { "200": { "description": "For action=sale: what to send. For action=check: the payment status.", "content": { "application/json": { "schema": { "oneOf": [ { "$ref": "#/components/schemas/Sale" }, { "type": "object", "properties": { "status": { "type": "string", "enum": [ "pending", "paid", "invalid" ] }, "message": { "type": "string" }, "explorer": { "type": "string", "description": "Block explorer link once paid." } } } ] } } } }, "400": { "description": "Unsupported coin or amount out of range" }, "410": { "description": "The payment token expired; open a new sale" }, "429": { "description": "Rate limited (30 sales per minute per IP)" } } } }, "/api/x402/pay": { "get": { "operationId": "x402Pay", "summary": "Pay a business or crypto domain with x402 (v2)", "description": "Without a payment header: HTTP 402 with a base64 PAYMENT-REQUIRED header (the same JSON is in the body) listing USDC 'exact' options on Base (eip155:8453), Polygon (eip155:137) and Arbitrum (eip155:42161), paid straight to the payee's wallet. Retry the same URL with a PAYMENT-SIGNATURE header (base64 x402 v2 PaymentPayload with an EIP-3009 authorization) and the payment is verified and settled through an x402 facilitator. POST works the same way.", "parameters": [ { "name": "to", "in": "query", "required": true, "schema": { "type": "string" }, "description": "XL Pay business code or crypto domain." }, { "name": "amount", "in": "query", "required": true, "schema": { "type": "number", "minimum": 0.01, "maximum": 25000 }, "description": "US dollars (USDC, 1:1). Ignored for fixed-price pay links." }, { "name": "note", "in": "query", "required": false, "schema": { "type": "string", "maxLength": 80 } }, { "name": "l", "in": "query", "required": false, "schema": { "type": "string" }, "description": "Signed pay-link token." }, { "name": "PAYMENT-SIGNATURE", "in": "header", "required": false, "schema": { "type": "string" }, "description": "Base64 x402 v2 PaymentPayload." } ], "responses": { "200": { "description": "Paid. Body: {paid, payee, usd, unit, network, transaction, payer, explorer}. PAYMENT-RESPONSE header carries the facilitator's settlement response." }, "402": { "description": "Payment required, or the payment was not valid (see error)." }, "404": { "description": "Unknown payee" }, "409": { "description": "Payee doesn't take USDC on Base, Polygon or Arbitrum; use /api/xlpay/pay" } } } } }, "components": { "schemas": { "RailId": { "type": "string", "enum": [ "solana", "base", "ethereum", "arbitrum", "polygon", "sui", "stellar", "solana_pyusd", "ethereum_pyusd", "arbitrum_pyusd", "sol", "eth", "eth_base", "btc", "xrp" ], "description": "Coin and network. solana/base/ethereum/arbitrum/polygon/sui/stellar = USDC on that network; *_pyusd = PYUSD; sol, eth (Ethereum), eth_base (ETH on Base), btc, xrp = native coins at the live rate." }, "Rail": { "type": "object", "properties": { "id": { "$ref": "#/components/schemas/RailId" }, "label": { "type": "string" }, "asset": { "type": "string" }, "network": { "type": "string" }, "group": { "type": "string", "enum": [ "stable", "coin" ] }, "speed": { "type": "string" } } }, "Sale": { "type": "object", "properties": { "token": { "type": "string", "description": "Pass to action=check. Valid for 24 hours." }, "to": { "type": "string", "description": "Receiving address. Send here." }, "amount": { "type": "string", "description": "Exact amount of unit to send. It is unique to this sale; do not round." }, "unit": { "type": "string", "description": "Asset to send, e.g. USDC, PYUSD, SOL, ETH, BTC, XRP." }, "network": { "type": "string" }, "tag": { "type": [ "integer", "null" ], "description": "XRP destination tag. Required for XRP." }, "uri": { "type": "string", "description": "Wallet payment URI (EIP-681, Solana Pay, SEP-7, BIP21 or XRP X-address) with the same details." }, "total": { "type": "number", "description": "US dollar total." }, "expires": { "type": "integer", "description": "Unix ms. Crypto prices are locked until then; send before it." } } } } } }