Multisig Signer Change Explainer

WHAT IT DOES

Multisig Signer Change Explainer decodes and explains proposed multisig signer changes before you sign or vote. The tool takes the multisig contract address and transaction calldata, identifies the operation type (add owner, remove owner, replace owner, or change threshold), extracts the signer address and threshold values from the calldata, and detects suspicious patterns including threshold reductions, adding unknown addresses, removing active signers, or changes that would reduce the number of signatures required. The tool then uses AI to generate a plain-language explanation of the signer change: who is being added or removed, how the signer set changes, what happens to the threshold, and whether the change appears legitimate or suspicious. Results include a risk level, operation type, signer address, current and proposed threshold, flags, and a comprehensive AI-generated explanation. The tool operates entirely read-only — no transactions are sent, no signatures are required. The AI explanation is designed to help you understand exactly what governance change you are approving before you sign.

HOW TO USE

Connect your EVM wallet using the "Connect" button in the header. Select the network where the multisig contract is deployed from the dropdown menu. Enter the multisig contract address. Paste the transaction calldata (hex string starting with 0x) from the pending signer change transaction. Optionally enter the proposed signer address if you know it — this helps the tool provide more accurate analysis. Click "Explain signer change" to begin the analysis. The tool decodes the calldata, identifies the operation type, extracts the signer address and threshold values, detects suspicious patterns, and sends the data to the AI for a plain-English signer change explanation. Results appear within seconds, showing the multisig contract, chain, risk level, operation type, signer address, current threshold, proposed threshold, flags, and a comprehensive AI-generated explanation written in clear, conversational language.

SIGNER CHANGE DECODING AND RISK DETECTION

The tool uses a signature-based decoding engine to analyze multisig signer changes. It extracts the first 4 bytes of the calldata as the function signature and matches it against a database of known signer change function signatures — including addOwner (0x7bd703e8), removeOwner (0x0d5820a7), changeRequirement (0x44b1b8f9), changeThreshold (0x7065cb48), and replaceOwner (0x44a9e5d4). For each recognized signature, the tool identifies the operation type and attempts to extract the signer address from the calldata parameters. For threshold changes, the tool extracts the proposed threshold value. The tool also scans for suspicious patterns including signer addresses with unusual patterns (0000, ffff), threshold reductions, and high-risk operation types. The AI receives all decoded data and is prompted to explain the signer change in plain language — stating who is being added or removed, how the signer set changes, what happens to the threshold, and whether the change appears routine or suspicious. The AI is also instructed to state plainly what it cannot verify — that it decodes calldata and reads on-chain data, not the proposer's intent, off-chain context, or the identity and trustworthiness of the proposed signer.

WHAT IT CANNOT SEE

This tool cannot definitively verify the true intent of a signer change — only decodes calldata and reads on-chain data. It cannot detect off-chain coordination or malicious intent not reflected in calldata — a signer change that appears benign could be part of a coordinated attack. The tool cannot predict whether the change will be approved or executed — it can only explain the proposed change. Legitimate signer changes may involve adding or removing signers for operational reasons — removals are not always malicious. The tool cannot verify the identity or trustworthiness of the proposed signer — it cannot check whether the address belongs to a legitimate person or entity. The tool cannot detect if the multisig contract has been compromised. The tool cannot detect if the proposer is acting maliciously. The tool cannot predict the outcome of the signer change. The tool cannot detect off-chain governance processes or social context that might make a signer change more or less suspicious. The tool cannot verify that the threshold change is appropriately set for the new signer configuration.

PLEASE NOTE

Multisig Signer Change Explainer supports EVM-compatible chains only (Ethereum, BSC, Polygon, Arbitrum, Optimism, Avalanche, and others). The tool is read-only and never requests wallet signatures or transaction approvals. Signer change explanations are AI-generated from calldata decoding — always verify the signer change details through the multisig contract's official interface and your wallet's transaction preview before signing. The AI explanation is for informational purposes only and does not constitute financial or legal advice. Never sign a multisig signer change you do not fully understand. Always verify the identity of any new signer through trusted communication channels before approving.