Multi-Call Batch Failure Isolator

WHAT IT DOES

Multi-Call Batch Failure Isolator is a developer-focused tool that isolates failed calls in multi-call batches by simulating each call individually and identifying the revert reasons. It takes batch call data as a JSON array of {target, data, value} objects, and optionally a transaction hash and contract ABI, then uses eth_call to simulate each call in the batch. The tool reports which calls succeeded and which failed, with detailed error messages for each failure. When a contract ABI is provided, the tool decodes function names from the calldata for better readability. Results are displayed with a summary showing total calls, pass count, and fail count, along with a detailed breakdown of each call's status, return value, or error message. This enables developers to quickly identify which call in a batch caused a transaction to revert, and understand the reason for the failure without manually inspecting the entire batch.

HOW TO USE

Connect your wallet to the target EVM chain. Enter batch call data as a JSON array of objects with "target", "data", and optional "value" fields. Optionally, enter a transaction hash for context and a contract ABI (JSON format) to decode function names. Click "Isolate failures" to simulate each call individually. The tool will display a summary with the number of calls, passed, and failed. Each call is shown with its index, function name (decoded if ABI is provided), target address, calldata, status (pass/fail), return value, or error message. The isolation report can be copied or downloaded as JSON.

TECHNICAL NOTE: INDIVIDUAL CALL SIMULATION AND ERROR ISOLATION

The tool processes each call in the batch by constructing a transaction object with the target address, calldata, and value, then executing it using eth_call. This simulates the call as if it were executed on-chain, without modifying state. When a call reverts, the tool captures the revert reason using the node's error message. If an ABI is provided, the tool attempts to decode the calldata to identify the function being called. The tool also supports transaction hash context to provide additional information about the original transaction. All calls are executed sequentially, and failures are isolated to the specific call that caused the revert, not the entire batch.

WHAT IT CANNOT SEE

The tool cannot isolate failures without batch call data or a transaction hash. It is limited to the accuracy of the provided ABI; without the correct ABI, function names cannot be decoded. It cannot decode custom error signatures without the correct ABI. The tool cannot analyze transactions on non-EVM chains. It cannot guarantee that all failures are correctly identified, as some failures may depend on the state of the blockchain at the time of simulation. The tool does not execute the batch as a single transaction; it simulates each call independently.

PLEASE NOTE

This tool is designed exclusively for EVM-compatible chains (Ethereum, Polygon, BNB Chain, Arbitrum, Optimism, Avalanche C-Chain, etc.). It does not support non-EVM blockchains. The tool is read-only and does not submit any transactions. The isolation results are based on simulations and may not perfectly match the behavior of the actual batch transaction. Always verify the isolated failures against the original transaction and contract logic. The tool provides no warranty that the isolation is complete or accurate; users should validate the findings with additional debugging tools.