Build an unsigned swap transaction for the best route
Build an unsigned swap transaction for the best route. Builds an unsigned transaction for the selected route. Compare it with a fresh quote, validate every returned transaction field, obtain explicit signing approval, and broadcast it through the selected chain's RPC. The compatibility parameters permit and usePermit2 are ignored. For an ERC-20 source, approve the router in tx.to for at least srcAmount before executing the returned transaction.
1000 (raw units)
price
7
calls / 30d
1
unique payers
2026-08-21
updated
Provider
3route.agents.bakingbad.dev · discovered, not yet claimed by its owner
Payment (x402 accepts[])
[
{
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"payTo": "AZ59bSccJmQu8Ljic1c5zxhjZitVbbutUYjBNwKLqfyD",
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"amount": "1000",
"maxTimeoutSeconds": 300
},
{
"scheme": "exact",
"network": "eip155:8453",
"payTo": "0x5D89060682fcE50eCaa7600aF6A5645Bd2b107Eb",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"amount": "1000",
"maxTimeoutSeconds": 300
},
{
"scheme": "batch-settlement",
"network": "eip155:8453",
"payTo": "0x5D89060682fcE50eCaa7600aF6A5645Bd2b107Eb",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"amount": "1000",
"maxTimeoutSeconds": 300
},
{
"scheme": "exact",
"network": "eip155:42793",
"payTo": "0x5D89060682fcE50eCaa7600aF6A5645Bd2b107Eb",
"asset": "0x796Ea11Fa2dD751eD01b53C372fFDB4AAa8f00F9",
"amount": "1000",
"maxTimeoutSeconds": 300
}
]Output schema
{
"bazaar": {
"info": {
"input": {
"method": "GET",
"pathParams": {
"chainId": "42793"
},
"queryParams": {
"amount": "1000000000000000000",
"dst": "0x2222222222222222222222222222222222222222",
"fee": 0,
"from": "0x1111111111111111111111111111111111111111",
"gasPrice": "1000000000",
"includeBlockNumber": false,
"includeProtocols": false,
"includeTokensInfo": false,
"isExactOutput": false,
"receiver": "0x1111111111111111111111111111111111111111",
"referrer": "0x1111111111111111111111111111111111111111",
"slippage": 1,
"src": "0x0000000000000000000000000000000000000000"
},
"type": "http"
},
"output": {
"example": {
"dstAmount": "950000",
"dstAmountMin": "940500",
"gas": 210000,
"srcAmount": "1000000000000000000",
"tx": {
"data": "0x1234",
"from": "0x1111111111111111111111111111111111111111",
"gas": "210000",
"gasPrice": "1000000000",
"to": "0x2222222222222222222222222222222222222222",
"value": "1000000000000000000"
}
},
"type": "json"
}
},
"routeTemplate": "/api/v6.1/:chainId/swap",
"schema": {
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"pathParams": {
"additionalProperties": false,
"properties": {
"chainId": {
"enum": [
"4663",
"42793",
"128064"
],
"example": "4663",
"pattern": "^[0-9]+$",
"type": "string"
}
},
"required": [
"chainId"
],
"type": "object"
},
"queryParams": {
"additionalProperties": false,
"properties": {
"amount": {
"example": "1000000000000000000",
"pattern": "^[0-9]+$",
"type": "string"
},
"dst": {
"example": "0x2222222222222222222222222222222222222222",
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
},
"excludedProtocols": {
"type": "string"
},
"fee": {
"default": 0,
"maximum": 3,
"minimum": 0,
"type": "number"
},
"from": {
"example": "0x1111111111111111111111111111111111111111",
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
},
"gasPrice": {
"example": "1000000000",
"pattern": "^[0-9]+$",
"type": "string"
},
"includeBlockNumber": {
"default": false,
"type": "boolean"
},
"includeProtocols": {
"default": false,
"type": "boolean"
},
"includeTokensInfo": {
"default": false,
"type": "boolean"
},
"isExactOutput": {
"default": false,
"type": "boolean"
},
"protocols": {
"type": "string"
},
"receiver": {
"example": "0x1111111111111111111111111111111111111111",
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
},
"referrer": {
"example": "0x1111111111111111111111111111111111111111",
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
},
"slippage": {
"default": 1,
"example": 1,
"maximum": 50,
"minimum": 0,
"type": "number"
},
"src": {
"example": "0x0000000000000000000000000000000000000000",
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
}
},
"required": [
"src",
"dst",
"amount",
"from"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}
},
"erc20ApprovalGasSponsoring": {
"info": {
"description": "The facilitator broadcasts a pre-signed ERC-20 approve() transaction to grant Permit2 allowance.",
"version": "1"
},
"schema": {
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"amount": {
"description": "The amount approved (uint256). Always MaxUint256.",
"pattern": "^[0-9]+$",
"type": "string"
},
"asset": {
"description": "The address of the ERC-20 token contract.",
"pattern": "^0x[a-fA-F0-9]{40}$",
"type": "string"
},
"from": {
"description": "The address of the sender (token owner).",
"pattern": "^0x[a-fA-F0-9]{40}$",
"type": "string"
},
"signedTransaction": {
"description": "The RLP-encoded signed EIP-1559 transaction as a hex string.",
"pattern": "^0x[a-fA-F0-9]+$",
"type": "string"
},
"spender": {
"description": "The address of the spender (Canonical Permit2).",
"pattern": "^0x[a-fA-F0-9]{40}$",
"type": "string"
},
"version": {
"description": "Schema version identifier.",
"pattern": "^[0-9]+(\\.[0-9]+)*$",
"type": "string"
}
},
"required": [
"from",
"asset",
"spender",
"amount",
"signedTransaction",
"version"
],
"type": "object"
}
}
}Use it
curl
curl "https://3route.agents.bakingbad.dev/api/v6.1/:chainId/swap" # -> 402 Payment Required, accepts[] lists how to pay # retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid
JavaScript
const res = await fetch("https://3route.agents.bakingbad.dev/api/v6.1/:chainId/swap");
if (res.status === 402) {
const { accepts } = await res.json();
// pay one of accepts[] via an x402 client, then retry with the payment header
}Python
import httpx
res = httpx.get("https://3route.agents.bakingbad.dev/api/v6.1/:chainId/swap")
if res.status_code == 402:
accepts = res.json()["accepts"]
# pay one of accepts[] via an x402 client, then retry with the payment headerMachine-readable
Everything on this page is also available as clean JSON at /resources/1231.json, and this resource appears in /discovery/resources and /discovery/search.