Nov 1, 2026 · 2 mins read
What a simulation proves, and what it does not
A clean eth_call says one thing about one block. That is useful and it is narrow.
Before the wallet opens, the site runs the exact transaction as a read against the newest block, from your address, and estimates its gas. Nothing is sent.
A clean result tells you
At this block, from this address, with these allowances and this balance, the call would not revert.
It does not tell you
That it will still be true when your transaction lands. That the token is well behaved. That you can sell it later. That the price is fair. Those are different questions.
A failed result
The site prints the reason when the contract gives one, and will not open your wallet for that transaction. The most common causes are a missing allowance, a low balance and a minimum the pool can no longer meet.