Transit API Reference

Base URL

Base URL: https://api.paxoslabs.com

All Transit endpoints are public and do not require authentication.

Response Format

The /v1/transit/orders/quote endpoint accepts a responseFormat query parameter:

`responseFormat`	`data` (hex)	`abi` / `functionName` / `args`	Use when
`encoded` (default)	Yes	No	Signer consumes raw `data` (`eth_sendTransaction`, HSM)
`full`	Yes	Yes	Debugging; need raw + decoded views
`structured`	No	Yes	Encode locally (viem `encodeFunctionData`)

Order Quote

GET /v1/transit/orders/quote Returns everything needed to submit a submitOrder transaction on-chain: the TransitStation address, ABI-encoded calldata, and ETH value for cross-chain messaging.

Request Parameters

Parameter	Type	Required	Description
`userAddress`	hex string	Yes	Wallet address receiving the want asset on the destination chain
`offerAmount`	decimal string	Yes	Amount of offer asset in base units. Minimum $35 USD equivalent.
`offerAsset`	hex string	Yes	Token contract address on source chain (debited)
`wantAsset`	hex string	Yes	Token contract address on destination chain (credited)
`sourceChainId`	integer	Yes	EVM chain ID of source chain (where tx is submitted)
`destinationChainId`	integer	Yes	EVM chain ID of destination chain
`permitSignature`	hex string (130 chars)	Conditional	EIP-2612 permit signature. Required if `permitDeadline` is provided.
`permitDeadline`	integer	Conditional	Unix timestamp. Required if `permitSignature` is provided.
`integratorFee`	decimal string	Conditional	Fee in offer-asset base units. Required if `integratorFeeReceiver` is provided.
`integratorFeeReceiver`	hex string	Conditional	Address to receive integrator fee. Required if `integratorFee` is provided.
`distributorCode`	hex string (64 chars)	Optional	32-byte code tagging order source (emitted on-chain). Defaults to organization’s configured distributor code.
`responseFormat`	enum	Optional	`encoded` (default), `full`, or `structured`

Response

{
  "transaction": {
    "to": "0x...",
    "data": "0x...",
    "value": "1500000000000000",
    "abi": [],
    "functionName": "submitOrder",
    "args": []
  },
  "amountOut": "49990000",
  "protocolFee": "10000",
  "integratorFee": "0",
  "totalFees": "10000",
  "estimatedLatencyMs": 300000
}

Field	Description
`transaction.to`	TransitStation contract address on source chain
`transaction.data`	ABI-encoded calldata (present when `responseFormat` is `encoded` or `full`)
`transaction.value`	ETH value to send (decimal string, wei). Covers cross-chain messaging fee.
`transaction.abi`	Solidity ABI fragment (present when `responseFormat` is `full` or `structured`)
`transaction.functionName`	`submitOrder` or `submitOrderWithPermit`
`transaction.args`	Positional arguments (BigInt values as decimal strings)
`amountOut`	Net credit in want-asset base units after fees
`protocolFee`	Protocol fee in offer-asset base units
`integratorFee`	Integrator fee in offer-asset base units (`"0"` when none)
`totalFees`	Sum of `protocolFee` + `integratorFee`
`estimatedLatencyMs`	Estimated delivery time in milliseconds (undefined if no SLA data)

On-Chain Structs

The args array contains the Quote struct and signature:

struct Route {
  uint32 destEID;
  address offerAsset;
  address wantAsset;
}

struct Quote {
  Route route;
  uint256 offerAmount;
  address receiver;
  uint256 protocolFee;
  uint256 integratorFee;
  address integratorFeeReceiver;
  bytes32 distributorCode;
  uint256 deadline;
  bytes32 salt;
}

function submitOrder(Quote quote, bytes signature) payable returns (bytes32 uuid)

function submitOrderWithPermit(
  Quote quote,
  bytes signature,
  uint256 permitDeadline,
  uint8 v,
  bytes32 r,
  bytes32 s
) payable returns (bytes32 uuid)

Example

curl "https://api.paxoslabs.com/v1/transit/orders/quote?\
userAddress=0x1234567890abcdef1234567890abcdef12345678&\
offerAmount=50000000&\
offerAsset=0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48&\
wantAsset=0x833589fcd6edb6e08f4c7c32d4f71b54bda02913&\
sourceChainId=1&\
destinationChainId=4663" \

Code Example (viem)

import { createWalletClient, http } from 'viem'
import { mainnet } from 'viem/chains'

const BASE = 'https://api.paxoslabs.com'

// 1. Fetch quote calldata
const url = new URL(`${BASE}/v1/transit/orders/quote`)
url.searchParams.set('userAddress', account.address)
url.searchParams.set('offerAmount', '50000000') // $50 USDC
url.searchParams.set('offerAsset', USDC_ETH)
url.searchParams.set('wantAsset', USDG_RH)
url.searchParams.set('sourceChainId', '1')
url.searchParams.set('destinationChainId', '4663')

const { transaction: tx } = await fetch(url).then((r) => r.json())

// 2. Submit order (value covers messaging fee)
await walletClient.sendTransaction({
  to: tx.to as `0x${string}`,
  data: tx.data as `0x${string}`,
  value: BigInt(tx.value),
  chain: mainnet,
  account,
})

Routes

GET /v1/transit/routes Lists available Transit routes for the caller’s organization.

Request Parameters

Parameter	Type	Required	Description
`filter`	string	Optional	AIP-160 filter expression. Keys: `sourceChainId`, `destinationChainId`, `offerAsset`, `wantAsset`

Response

{
  "routes": [
    {
      "sourceChainId": 1,
      "destinationChainId": 4663,
      "destinationChainEID": 40451,
      "offerAsset": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
      "wantAsset": "0x...",
      "minOrderSize": "35000000",
      "tokenMetadataMap": {
        "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48": {
          "chain_id": "1",
          "address": "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48",
          "name": "USD Coin",
          "symbol": "USDC",
          "decimals": "6",
          "token_standard": "ERC20"
        }
      }
    }
  ]
}

Field	Description
`sourceChainId`	EVM chain ID of source chain
`destinationChainId`	EVM chain ID of destination chain
`destinationChainEID`	Endpoint ID of destination chain
`offerAsset`	Token address on source chain
`wantAsset`	Token address on destination chain
`minOrderSize`	Minimum order size in offer-asset base units
`tokenMetadataMap`	Token metadata keyed by lowercase address

Get Order

GET /v1/transit/orders/:orderId Returns indexer-backed status and details for a single Transit order.

Path Parameters

Parameter	Type	Description
`orderId`	hex string (64 chars)	32-byte order ID (from `OrderSubmitted` event)

Response

{
  "order": {
    "id": "0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef",
    "offerAsset": "0x...",
    "wantAsset": "0x...",
    "amountDue": "50000000",
    "remainingAmountDue": "0",
    "offerAmount": "50000000",
    "receiver": "0x...",
    "distributorCode": "0x0000...0000",
    "destinationChainId": 4663,
    "sourceChainId": 1,
    "receiveTime": 1234567890,
    "status": "PROCESSED",
    "user": "0x...",
    "createdAt": "2026-01-01T00:00:00Z",
    "updatedAt": "2026-01-01T00:05:00Z",
    "tokenMetadata": {},
    "orderExecuteds": [
      {
        "id": "0xabcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890",
        "amount": "50000000",
        "remaining": "0",
        "timestamp": 1234567890,
        "txHash": "0x...",
        "chainId": 4663
      }
    ]
  }
}

Order Status Values

Status	Meaning
`PENDING_BRIDGE`	Order submitted, awaiting bridge processing
`PROCESSING`	Order is being processed
`PROCESSED`	Order fulfilled
`REMOVED`	Order removed

List Orders

GET /v1/transit/orders Returns a paginated list of orders for a user address.

Request Parameters

Parameter	Type	Required	Description
`userAddress`	hex string	Yes	User wallet address to filter by
`pageSize`	integer	Optional	Results per page (default: 10, max: 100)
`pageToken`	string	Optional	Opaque cursor for next page
`filter`	string	Optional	AIP-160 filter expression. Keys: `offerAsset`, `wantAsset`, `sourceChain`, `destinationChain`, `status`

Response

{
  "orders": [],
  "nextPageToken": "opaque-cursor"
}

Error Handling

{
  "error": {
    "code": 400,
    "message": "Order amount is below the minimum of $35",
    "status": "INVALID_ARGUMENT"
  }
}

HTTP	`error.status`	Action
400	`INVALID_ARGUMENT`	Fix request (e.g., increase offer amount)
404	`NOT_FOUND`	Order or route not found
503	`INTERNAL`	Retry with exponential backoff

Common Errors

Issue	Error	Fix
Offer amount below $35 USD	`400 INVALID_ARGUMENT`	Increase offer amount
Missing `permitDeadline` with `permitSignature`	`400 INVALID_ARGUMENT`	Provide both or neither
Missing `integratorFeeReceiver` with `integratorFee`	`400 INVALID_ARGUMENT`	Provide both or neither
Invalid `distributorCode` length	`400 INVALID_ARGUMENT`	Must be 32 bytes (0x + 64 hex chars)
Insufficient ETH for `value`	On-chain revert	Ensure wallet has ETH to cover `transaction.value`
Route not available	`404 NOT_FOUND`	Check `/v1/transit/routes` for available pairs

Supported Chains

Chain	ID
Ethereum	1
RH Chain	4663

​Base URL

​Response Format

​Order Quote

​Request Parameters

​Response

​On-Chain Structs

​Example

​Code Example (viem)

​Routes

​Request Parameters

​Response

​Get Order

​Path Parameters

​Response

​Order Status Values

​List Orders

​Request Parameters

​Response

​Error Handling

​Common Errors

​Supported Chains

Base URL

Response Format

Order Quote

Request Parameters

Response

On-Chain Structs

Example

Code Example (viem)

Routes

Request Parameters

Response

Get Order

Path Parameters

Response

Order Status Values

List Orders

Request Parameters

Response

Error Handling

Common Errors

Supported Chains