trace_callMany

Traces multiple calls in sequence on Base, where each call can depend on the state changes of the previous one.

Archive Node Required

This method requires an archive node. It is not available on full nodes.

Use Cases

• Multi-step simulation - Simulate a sequence of dependent transactions
• Arbitrage analysis - Test multi-hop swap paths
• Batch operations - Preview multiple contract interactions for consumer dApps, SocialFi, NFT marketplaces, and merchant payment integrations

Parameters

Parameter	Type	Required	Description
calls	Array	Yes	Array of [callObject, traceTypes] pairs
blockNumber	QUANTITY|TAG	No	Block number or tag (default: latest)

Each element in calls is a tuple of:

• callObject - Transaction call object (from, to, gas, value, data)
• traceTypes - Array of trace types: ["trace"], ["vmTrace"], ["stateDiff"]

Request

{
  "jsonrpc": "2.0",
  "method": "trace_callMany",
  "params": [
    [
      [{"to": "0x4200000000000000000000000000000000000006", "data": "0x70a082310000000000000000000000004200000000000000000000000000000000000006"}, ["trace"]],
      [{"to": "0x4200000000000000000000000000000000000006", "data": "0x18160ddd"}, ["trace"]]
    ],
    "latest"
  ],
  "id": 1
}

Code Examples

cURL

curl -X POST https://api-base-mainnet-archive.n.dwellir.com/YOUR_API_KEY \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "trace_callMany",
    "params": [
      [
        [{"to": "0x4200000000000000000000000000000000000006", "data": "0x70a082310000000000000000000000004200000000000000000000000000000000000006"}, ["trace"]],
        [{"to": "0x4200000000000000000000000000000000000006", "data": "0x18160ddd"}, ["trace"]]
      ],
      "latest"
    ],
    "id": 1
  }'

JavaScript

import { JsonRpcProvider } from 'ethers';

const provider = new JsonRpcProvider('https://api-base-mainnet-archive.n.dwellir.com/YOUR_API_KEY');

const results = await provider.send('trace_callMany', [
  [
    [{ to: '0x4200000000000000000000000000000000000006', data: '0x70a082310000000000000000000000004200000000000000000000000000000000000006' }, ['trace']],
    [{ to: '0x4200000000000000000000000000000000000006', data: '0x18160ddd' }, ['trace']]
  ],
  'latest'
]);
console.log('Call results:', results.length);
for (const result of results) {
  console.log('  Output:', result.output);
}

Python

from web3 import Web3

w3 = Web3(Web3.HTTPProvider('https://api-base-mainnet-archive.n.dwellir.com/YOUR_API_KEY'))

results = w3.provider.make_request('trace_callMany', [
    [
        [{'to': '0x4200000000000000000000000000000000000006', 'data': '0x70a082310000000000000000000000004200000000000000000000000000000000000006'}, ['trace']],
        [{'to': '0x4200000000000000000000000000000000000006', 'data': '0x18160ddd'}, ['trace']]
    ],
    'latest'
])
for i, result in enumerate(results['result']):
    print(f'Call {i}: output={result.get("output", "N/A")}')

Related Methods

• trace_call - Trace a single call
• eth_call - Execute call without trace