Cross-Chain Transfers

PAXGy moves between Ethereum mainnet and X Layer over Chainlink CCIP. The tokens are burned on the source chain and issued on the destination. There is no wrapped representation and no liquidity pool. Two flows:

Transfer. Move PAXGy you already hold, in either direction. GET /v2/amplify/bridge
Mint and transfer. Deposit PAXG on Ethereum and receive PAXGy on X Layer, in one transaction. GET /v2/amplify/deposit with cross-chain parameters

PAXG exists only on Ethereum, so minting and redemption are Ethereum-only. Transfers move PAXGy in both directions, but to redeem, the PAXGy has to come back to Ethereum first.

Transferring held PAXGy

curl -G "https://api.paxoslabs.com/v2/amplify/bridge" \
  -H "x-api-key: pxl_your_key" \
  --data-urlencode "vaultAddress=0x6c6494Fd9962eB98B94ffA48F6679058F820700e" \
  --data-urlencode "shareAmount=1000000000000000000" \
  --data-urlencode "userAddress=0xYourWallet" \
  --data-urlencode "chainId=1" \
  --data-urlencode "destinationChainId=196" \
  --data-urlencode "messageGas=100000"

Parameters

Parameter	Type	Required	Description
`vaultAddress`	`string`	Yes	The PAXGy token address
`shareAmount`	`string`	Yes	PAXGy to move, in base units
`userAddress`	`string`	Yes	Wallet sending the transaction
`chainId`	`number`	Yes	Source chain
`destinationChainId`	`number`	Yes	Destination chain: `1` for Ethereum, `196` for X Layer
`destinationChainReceiver`	`string`	No	Who receives the PAXGy on the destination chain. Defaults to `userAddress`
`messageGas`	`string`	Yes	Gas to buy for execution on the destination chain

Response

{
  "transaction": {
    "to": "0x41AB5d8387e60E30AACCF11357C306f6d875A6f7",
    "data": "0x...",
    "value": "431000000000000"
  },
  "fee": {
    "raw": "431000000000000",
    "formatted": "0.000431",
    "decimals": 18
  },
  "lane": {
    "destinationChainId": 196,
    "targetTeller": "0x41AB5d8387e60E30AACCF11357C306f6d875A6f7",
    "minimumMessageGas": "0",
    "messageGasLimit": "100000"
  }
}

The delivery fee must be exact

Cross-chain delivery costs a fee in the source chain’s native token, on top of gas. It is already set as transaction.value, and fee reports the same number for display.

Send transaction.value exactly as returned. The transaction is rejected on-chain if the value differs at all, including if it is too high, so padding it “to be safe” will fail. The quote is priced at the current block and moves with gas conditions: request it again if the user does not confirm promptly.

Show fee.formatted in your confirmation UI. A user approving a transfer sees a native-token charge they did not ask for otherwise.

const hash = await walletClient.sendTransaction({
  to: prepared.transaction.to,
  data: prepared.transaction.data,
  value: BigInt(prepared.transaction.value), // exact, never rounded or padded
  chainId: 1,
})

Choosing `messageGas`

messageGas buys execution on the destination chain. Each route accepts a range, returned on every response:

prepared.lane.minimumMessageGas // "0"
prepared.lane.messageGasLimit   // "100000"

A value outside that range returns a 400 naming both bounds, so you can correct it without guessing. If you have no reason to pick otherwise, request messageGasLimit.

Minting onto X Layer

Because PAXG only exists on Ethereum, the mint leg always starts there, so chainId is 1. Pass the cross-chain fields to have the PAXGy issued on X Layer instead of Ethereum, in the same transaction:

curl -G "https://api.paxoslabs.com/v2/amplify/deposit" \
  -H "x-api-key: pxl_your_key" \
  --data-urlencode "vaultAddress=0x6c6494Fd9962eB98B94ffA48F6679058F820700e" \
  --data-urlencode "depositAsset=0x45804880De22913dAFE09f4980848ECE6EcbAf78" \
  --data-urlencode "depositAmount=1000000000000000000" \
  --data-urlencode "userAddress=0xYourWallet" \
  --data-urlencode "chainId=1" \
  --data-urlencode "destinationChainId=196" \
  --data-urlencode "messageGas=100000"

Three differences from a plain mint:

transaction.value carries the delivery fee, with the same exactness rule.
No mint fee applies on this route.
to and permitSignature are rejected with a 400. The PAXGy is issued on the destination chain, so a source-chain to cannot be honoured. Use destinationChainReceiver instead. And a single transaction cannot both consume a permit and transfer across chains, so approve PAXG first.

Errors

Status	Cause
`400`	No route open to `destinationChainId`, `messageGas` outside the accepted range, or `to` / `permitSignature` combined with `destinationChainId`
`403`	This wallet is not permitted to move PAXGy across chains
`503`	The chain is unreachable and the fee could not be priced

A 403 is a property of the wallet, not a transient failure, so retrying will not help. Cross-chain transfers are enabled per address as part of access approval.

Settlement time

The source transaction confirming does not mean the PAXGy has arrived. CCIP finalizes on its own schedule, and the destination balance appears after that. Model the gap explicitly: show the transfer as in-flight and poll the destination balance rather than assuming completion on the source receipt.

Minting

Deposit PAXG and receive PAXGy.

Direct Contract

The same transfer without the API.

Getting started

Amplify

PAXGy

Transit

USDG0

Webhooks

Cross-Chain Transfers

Transferring held PAXGy

Parameters

Response

The delivery fee must be exact

Choosing `messageGas`

Minting onto X Layer

Errors

Settlement time

Next

Minting

Direct Contract

​Transferring held PAXGy

​Parameters

​Response

​The delivery fee must be exact

​Choosing messageGas

​Minting onto X Layer

​Errors

​Settlement time

​Next

Minting

Direct Contract

Transferring held PAXGy

Parameters

Response

The delivery fee must be exact

Choosing `messageGas`

Minting onto X Layer

Errors

Settlement time

Next