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POST
/
{network}
/
calldata
{
  "success": true,
  "route": {
    "inputToken": {},
    "outputToken": {},
    "inputAmount": "<string>",
    "outputAmount": "<string>",
    "time": 123,
    "route": [
      {}
    ]
  },
  "swap_parameters": [
    {
      "token_in": "<string>",
      "token_out": "<string>",
      "rate": "<string>",
      "protocol_id": "<string>",
      "pool_address": "<string>"
    }
  ],
  "calldata": "<string>",
  "to": "<string>",
  "value": "<string>"
}

​
Overview

The Calldata endpoint combines the functionality of both /route and /execute endpoints, providing an optimized way to get transaction calldata in a single API call. This is ideal for applications that want to minimize API calls and latency.

​
Supported Networks

  • Base
  • HyperEVM
  • Scroll
  • Monad
  • Starknet
https://api.fibrous.finance/base/calldata

​
Request Body Parameters

​
amount
string
required
The amount of input tokens in wei format.Example: "1000000000000000000" for 1 token with 18 decimals
​
tokenInAddress
string
required
The contract address of the input token.
​
tokenOutAddress
string
required
The contract address of the output token.
​
slippage
number
default:"0.5"
required
Maximum acceptable slippage in percentage (0.1 to 100).
​
destination
string
required
The destination address to receive the output tokens.
​
excludeProtocols
string[]
Array of protocol IDs to exclude from routing.
​
direct
boolean
default:"false"
If true, only direct swaps will be considered.

​
Response

This endpoint combines the route and execute responses:
​
success
boolean
Indicates if the route was successfully found
​
route
object
Complete route information (same as /route endpoint)
​
swap_parameters
object[]
Swap parameters for execution
​
calldata
string
The encoded transaction calldata ready for execution
​
to
string
The Fibrous Router contract address
​
value
string
The amount of native token to send with the transaction

​
Example Request

curl -X POST "https://api.fibrous.finance/base/calldata" \
  -H "Content-Type: application/json" \
  -d '{
    "amount": "1000000000000000000",
    "tokenInAddress": "0x0000000000000000000000000000000000000000",
    "tokenOutAddress": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "slippage": 0.5,
    "destination": "0x1234567890123456789012345678901234567890"
  }'

​
Example Response

{
  "success": true,
  "route": {
    "inputToken": {
      "name": "Wrapped Ether",
      "address": "0x4200000000000000000000000000000000000006",
      "decimals": 18,
      "price": 3171.37
    },
    "outputToken": {
      "name": "USD Coin",
      "address": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
      "decimals": 6,
      "price": 0.99971
    },
    "inputAmount": "1000000000000000000",
    "outputAmount": "3165007379",
    "time": 0.495,
    "route": [
      {
        "percent": "51%",
        "swaps": [[...]]
      }
    ]
  },
  "swap_parameters": [
    {
      "token_in": "0x4200000000000000000000000000000000000006",
      "token_out": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
      "rate": "3165007379",
      "protocol_id": "9",
      "pool_address": "0x72ab388e2e2f6facef59e3c3fa2c4e29011c2d38"
    }
  ],
  "calldata": "0x...",
  "to": "0x274602a953847d807231d2370072f5f4e4594b44",
  "value": "1000000000000000000"
}

​
When to Use This Endpoint

Use Calldata

  • Single-step swap execution
  • Minimizing API calls
  • Reducing latency
  • Simple integrations

Use Route + Execute

  • Need to display route preview
  • User confirmation required
  • Complex routing logic
  • Custom route manipulation

​
Best Practices

  1. Token Approvals
    • Check token allowance before calling
    • Approve Fibrous Router to spend tokens
    • Not needed for native token swaps
  2. Transaction Execution
    • Use the exact to, calldata, and value from response
    • Set appropriate gas limit (use estimatedGas + buffer)
    • Monitor transaction status after submission
  3. Error Handling
    • Implement retry logic for failed requests
    • Handle insufficient liquidity gracefully
    • Validate addresses before calling

​
Complete Integration Example

import { ethers } from 'ethers';

async function executeSwap(provider, signer) {
  // 1. Get calldata
  const response = await fetch('https://api.fibrous.finance/base/calldata', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      amount: '1000000000000000000',
      tokenInAddress: '0x0000000000000000000000000000000000000000',
      tokenOutAddress: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913',
      slippage: 0.5,
      destination: await signer.getAddress()
    })
  });
  
  const data = await response.json();
  
  // 2. Execute transaction
  const tx = await signer.sendTransaction({
    to: data.to,
    data: data.calldata,
    value: data.value,
    gasLimit: Math.floor(Number(data.estimatedGas) * 1.2) // 20% buffer
  });
  
  // 3. Wait for confirmation
  const receipt = await tx.wait();
  console.log('Swap completed:', receipt.transactionHash);
  
  return receipt;
}

​
Network-Specific Router Addresses

  • Base
  • HyperEVM
  • Scroll
  • Starknet
Router: 0x... (included in response)
Router addresses are always included in the API response. No need to hardcode them in your application.