TL;DRA transaction is just a target address and some bytes. The first four bytes pick the function; the rest are its arguments. Before signing a revoke, check three things: the target is the token, the function is the zeroing one, and the amount is zero.
Anatomy of a revoke
Take a token allowance. The target is the token contract. The call data starts with 0x095ea7b3, the selector of approve(address,uint256). Then come two 32-byte words: the spender's address, padded with zeros on the left, and the amount, which for a revoke is all zeros.
Nullo prints the function signature, each argument and the raw bytes side by side, so you can match them against what your wallet shows.
Check it twice
Your wallet is the last word, not this site. A good wallet decodes approve calls and shows the spender and the new amount. If what it shows does not match the row you picked, cancel. A revoke never needs to send ETH, so the value should be zero as well.
One at a time, or one batch you can read
The revoke queue runs one transaction at a time. After each confirmation the state is read again from the chain, and the next row only opens when you ask for it. Nothing is signed for you.
If your wallet supports atomic batches (EIP-5792), the queue also offers one signature for every row. The batch holds exactly the calls listed in the queue, runs all of them or none, and every row is read again from the chain afterwards. Your wallet should list each call before you confirm.
Try it on your own address
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