🛠️ debug_traceCallMany RPC Method (Base Chain)

The debug_traceCallMany method simulates multiple bundles of transactions and returns detailed traces — without sending anything to the blockchain.

It's like eth_callMany, but returns full debug traces so you can see exactly what happens inside each call.

Parameters

1. bundles [required]

This is an array of transaction bundles. Each bundle includes:

• transactions: An array of transaction objects (just like in eth_call)
• blockOverride (optional): You can override the default block context:
  • blockNumber: Custom block number for the simulation
  • blockHash: Custom block hash (can be used in contracts via BLOCKHASH)
  • coinbase: Custom miner address
  • timestamp: Custom block timestamp
  • difficulty: Custom block difficulty
  • gasLimit: Custom block gas limit
  • baseFee: Custom base fee

2. simulation context [required]

Controls when and where the simulation happens:

• blockNumber or Tag: Choose "latest", "earliest", "pending", "safe", "finalized", or a hex block number
  🔒 Note: "safe" and "finalized" only work on Ethereum and Arbitrum

• transactionIndex: Where the simulated txs appear in the block. Default is -1, which means they run after the real txs.

3. state overrids [optional]

If you want to override specific accounts’ balance or code during the simulation, use this.

{
  "0xAddress": {
    "balance": "0xDE0B6B3A7640000" // 1 ETH
  }
}

4. timeout [optional]

The max simulation time in milliseconds (default: 5000 ms). Use this if simulating a large number of complex calls.

5. trace type [optional]

Use a tracer for more advanced introspection:

• tracer: "callTracer" or "prestateTracer"
  • "callTracer" - The calltracer keeps track of all call frames, including depth 0 calls, that are made during a transaction.
  • "prestateTracer" - The prestateTracer replays the transaction and tracks every part of state that occured during the transaction
• tracerConfig:
  • onlyTopCall: If true, skips sub-calls for faster output. When set to true, this will only trace the primary (top-level) call and not any sub-calls. It eliminates the additional processing for each call frame.

Returns

The return is the same structure as debug_traceCall (opens in a new tab), except you get an array of traces — one for each bundle/transaction.

callTracer response

prestateTracer response

For each contract touched:

• balance: Contract balance in wei
• code: Contract bytecode
• nonce: Contract nonce
• storage: Key-value mapping of storage slots

struct/opcode response (default if no tracer used)

Shows low-level execution logs:

• failed: Was execution successful?
• gas: Total gas used
• returnValue: Output of the call
• structLogs: Opcode trace steps:
  • pc, op, gas, gasCost, depth
  • stack, storage, memory
  • refund, error

Request

POST https://base-mainnet.chainnodes.org/YOUR-API-KEY

Example

curl https://base-mainnet.chainnodes.org/YOUR-API-KEY \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"debug_traceCallMany","params":[[{"transactions":[{"from":"0xDAFEA492D9c6733ae3d56b7Ed1ADB60692c98Bc5","to":"0xdAC17F958D2ee523a2206206994597C13D831ec7","gas":"0x92c0","gasPrice":"0x7896e72a000","value":"0x0","data":"0x70a0823100000000000000000000000047ac0fb4f2d84898e4d9e7b4dab3c24507a6d503"}],"blockOverride":{"blockNumber":"0xe39dd0"}}],{"blockNumber":"0x103434E","transactionIndex":234},{}],"id":1}'

Sample Response

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": [
    [
      {
        "structLogs": [
          {
            "pc": 0,
            "op": "PUSH1",
            "gas": 16136,
            "gasCost": 3,
            "depth": 1,
            "stack": [],
            "memory": []
          },
          {
            "pc": 2,
            "op": "PUSH1",
            "gas": 16133,
            "gasCost": 3,
            "depth": 1,
            "stack": ["0x60"],
            "memory": []
          },
          {
            "pc": 4,
            "op": "MSTORE",
            "gas": 16130,
            "gasCost": 12,
            "depth": 1,
            "stack": ["0x60", "0x40"],
            "memory": [
              "0000000000000000000000000000000000000000000000000000000000000000",
              "0000000000000000000000000000000000000000000000000000000000000000"
            ]
          }
        ]
      }
    ]
  ]
}