API documentation

GET /rates/fixed.xml

Public FixedFloat-shaped XML of all online pairs. No API key, no signature, no weight cost. We do not expose /rates/float.xml (float rate type is unsupported).

Parameters: none.

Fields per <item>

Example (live shape — SOL → BTCLN)

<rates>
  <item>
    <from>SOL</from>
    <to>BTCLN</to>
    <in>1</in>
    <out>0.00117230</out>
    <amount>0.00320351</amount>
    <tofee>0.00000200 BTCLN</tofee>
    <minamount>0.02500000 SOL</minamount>
    <maxamount>1.35281076 SOL</maxamount>
  </item>
  …
</rates>

Sample captured from a Lightning Swap exercise run against a live rates feed.

POST /api/v2/ccies

Currency catalog with FixedFloat field names. Pay-in assets have recv=1; Lightning payout is BTCLN with send=1.

Body: {} (sign that object). Weight: 1.

Response fields

Example response (trimmed)

{
  "code": 0,
  "msg": "OK",
  "data": [
    {
      "code": "SOL",
      "coin": "SOL",
      "network": "SOL",
      "name": "Solana",
      "recv": 1,
      "send": 0,
      "tag": null,
      "contract": null,
      "priority": 0,
      "logo": "https://lightning-swap.com/assets/images/coins/svg/sol.svg",
      "color": "#a364fc"
    },
    {
      "code": "USDTTRC",
      "coin": "USDT",
      "network": "TRX",
      "name": "Tether (TRC20)",
      "recv": 1,
      "send": 0,
      "tag": null,
      "contract": "TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t",
      "priority": 4,
      "logo": "https://lightning-swap.com/assets/images/coins/svg/usdttrc.svg",
      "color": "#53ae94"
    },
    {
      "code": "BTCLN",
      "coin": "BTC",
      "network": "LN",
      "name": "Bitcoin (Lightning)",
      "recv": 0,
      "send": 1,
      "tag": null,
      "contract": null,
      "priority": 0,
      "logo": "https://lightning-swap.com/assets/images/coins/svg/btcln.svg",
      "color": "#9157ff"
    }
  ]
}

POST /api/v2/price

Quote a pair. Use before create to show the user what they will pay / receive. Only type=fixed is supported. Both direction=from and direction=to work. Weight: 1.

Parameters

Affiliate params (refcode, afftax) and FixedFloat extras (ccies, usd) are ignored / not implemented.

Example — direction to (real exercise quote)

// Request
{
  "type": "fixed",
  "fromCcy": "SOL",
  "toCcy": "BTCLN",
  "direction": "to",
  "amount": "0.00004243"
}

// Response
{
  "code": 0,
  "msg": "OK",
  "data": {
    "from": {
      "code": "SOL",
      "network": "SOL",
      "coin": "SOL",
      "amount": 0.03815503,
      "rate": 0.00116446,
      "precision": 8,
      "min": 0.025,
      "max": 0.91611682,
      "usd": 2.9,
      "btc": 0.00004488
    },
    "to": {
      "code": "BTCLN",
      "network": "LN",
      "coin": "BTC",
      "amount": 0.00004243,
      "rate": 858.76715387,
      "precision": 8,
      "min": 0.00002711,
      "max": 0.00106478,
      "usd": 2.74
    },
    "errors": []
  }
}

data.errors values

POST /api/v2/create

Binding order create. Cost: 50 weight. Payout is always a Lightning invoice you supply — there is no on-chain BTC payout path.

Parameters

Idempotency (Lightning Swap extension)

Optionally send header Idempotency-Key: <opaque string> (or body field idempotency_key). A repeated create with the same key on the same account returns the original order instead of opening a second deposit.

Example — create (SOL → Lightning, from exercise)

// Request
{
  "type": "fixed",
  "fromCcy": "SOL",
  "toCcy": "BTCLN",
  "direction": "to",
  "amount": "0.00004243",
  "toAddress": "lnbc42430n1p49elex…cplvlg2n"
}

// Response (trimmed)
{
  "code": 0,
  "msg": "OK",
  "data": {
    "id": "QBSPEO",
    "type": "fixed",
    "email": "",
    "status": "NEW",
    "time": {
      "reg": 1784479529,
      "start": null,
      "finish": null,
      "update": 1784479529,
      "expiration": 1784480129,
      "left": 600
    },
    "from": {
      "code": "SOL",
      "coin": "SOL",
      "network": "SOL",
      "name": "Solana",
      "alias": "solana",
      "amount": "0.03815503",
      "address": "DTJnkqp4Uxx4ccpzLqSnaRtoescQRgpm1s5Pra3LesXF",
      "tag": "",
      "tagName": null,
      "tx": {
        "id": null,
        "amount": null,
        "fee": null,
        "ccyfee": null,
        "timeReg": null,
        "timeBlock": null,
        "confirmations": null
      },
      "addressAlt": null,
      "reqConfirmations": 1,
      "maxConfirmations": 16
    },
    "to": {
      "code": "BTCLN",
      "coin": "BTC",
      "network": "LN",
      "name": "Bitcoin (Lightning)",
      "alias": "lightning",
      "amount": "0.00004243",
      "address": "lnbc42430n1p49elex…cplvlg2n",
      "tag": "",
      "tagName": null,
      "tx": { "id": null, "amount": null, "fee": null, "ccyfee": null,
              "timeReg": null, "timeBlock": null, "confirmations": null }
    },
    "back": {
      "code": "",
      "amount": null,
      "address": "",
      "tx": { "id": null, "amount": null, "fee": null, "ccyfee": null,
              "timeReg": null, "timeBlock": null, "confirmations": null }
    },
    "emergency": { "status": [], "choice": "NONE", "repeat": "0" },
    "token": "ls7c2edffd2acd0be11bb1b6983975d7dc8d2945400a5b012b"
  }
}

Persist data.id and data.token — both are required for /order and /emergency. Show the payer from.address, from.amount, and from.tag when present. Deposit window is typically ~10 minutes (time.left at create).

Order object fields (create & order share this shape)

POST /api/v2/order

Fetch the latest order snapshot. Same data shape as create. Weight: 1.

Parameters

Example — completed order (poll after deposit + Lightning pay)

// Request
{ "id": "QBSPEO", "token": "ls7c2edffd2acd0be11bb1b6983975d7dc8d2945400a5b012b" }

// Response data (highlights)
{
  "id": "QBSPEO",
  "status": "DONE",
  "time": {
    "reg": 1784479529,
    "start": 1784479622,
    "finish": 1784479625,
    "update": 1784479625,
    "expiration": 1784480129,
    "left": 502
  },
  "from": {
    "code": "SOL",
    "amount": "0.03815503",
    "address": "DTJnkqp4Uxx4ccpzLqSnaRtoescQRgpm1s5Pra3LesXF",
    "tx": {
      "id": "5jFuRUiLFRK3LFdghA6BVx5KkT5b58uhSWqDqmu5wJrwngKNoq8by7i7DPi55Vuwq8GyNk7yBdctM2K4oBNnHdP8",
      "amount": "0.03815503",
      "fee": "0.00000635",
      "ccyfee": "SOL",
      "timeReg": 1784479622,
      "timeBlock": 1784479622,
      "confirmations": "12"
    },
    "reqConfirmations": 1,
    "maxConfirmations": 16
  },
  "to": {
    "code": "BTCLN",
    "amount": "0.00004243",
    "tx": {
      "id": "dd57894b0f721cfa593857f69efd10ce920f0a7710f7deb73782004d19664ac1",
      "amount": "0.00004243",
      "fee": "0.00000011",
      "ccyfee": "BTC",
      "timeReg": 1784479625,
      "timeBlock": 1784479625,
      "confirmations": "1"
    }
  },
  "emergency": { "status": [], "choice": "NONE", "repeat": "0" },
  "token": "ls7c2edffd2acd0be11bb1b6983975d7dc8d2945400a5b012b"
}

When status=DONE after a successful swap, to.tx.id is the Lightning payment preimage/hash identifier for the payout.

POST /api/v2/emergency

Choose an action when status is EMERGENCY. Lightning Swap supports refund only — choice=EXCHANGE is rejected because payout is a fixed BOLT11 amount and cannot be continued at a new market rate. Weight: 1.

Parameters

Response

Success returns a boolean data (FixedFloat-compatible) — not the order object. Poll /order for refund progress (back.address, back.tx, then DONE).

// Request (classic underpay → refund)
{
  "id": "WJ3IYG",
  "token": "ls2e2ac023d09704e467cbbf3d620ea54f5a315c04582770eb",
  "choice": "REFUND",
  "address": "BfMe1deFYJwaSeD9XoN1X8xw1PtcYjginrbvkQjS9w9U"
}

// Response
{ "code": 0, "msg": "", "data": true }

Idempotent: repeating the same refund address after success returns success again. A different address after submit returns 409.