Replay a Transaction

Replay one transaction with debug_traceTransaction and summarize the call tree.

Use execution replay-tx to inspect the call tree produced by a transaction.

The command calls debug_traceTransaction with the callTracer, flattens the nested calls, and prints gas, value, calldata size, and any call errors.

Command

rex execution replay-tx \
  --tx 0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Example Output

EXECUTION REPLAY TX

Tx:           0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
Calls:        3
Failed calls: 0
Max depth:    1

DEPTH TYPE         FROM                                       TO                                           VALUE        GAS   GAS USED IN BYTES OUT BYTES ERROR
    0 CALL         0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266 0x5fbdb2315678afecb367f032d93f642f64180aa3 0 wei     150000      48672       68         32 -
    1 STATICCALL   0x5fbdb2315678afecb367f032d93f642f64180aa3 0x0000000000000000000000000000000000000001 -          42112       3120        0         32 -

How It Works

debug_traceTransaction replays the transaction from the node’s stored chain state. The transaction must be available to the node, and the RPC endpoint must expose the debug namespace.

Start a local Reth node with debug RPC enabled:

reth node \
  --dev \
  --http \
  --http.api eth,net,web3,debug \
  --datadir ./alice

Field Notes

• Calls counts the flattened root call and all nested calls.
• Failed calls counts call frames with an error field.
• IN BYTES is calldata size for the call frame.
• OUT BYTES is returndata size for the call frame.
• VALUE is shown in wei or gwei using the same formatting as other Rex reports.