Risk warning system
16 rules, each one written down.
The transaction reverts
Any simulated call ends with status 0. The decoded reason (executor errors, Error(string), Panic) is shown.
Calldata to an address without code
The target's code size is 0 while calldata is not empty.
Function not decoded
The 4-byte selector is not in Delvo's list of known functions. Changes are still simulated.
Unlimited approval
An Approval event from you with an amount at or above 2^255.
Approval to an address without code
An Approval event from you to a spender whose code size is 0 (a plain account).
Approval to an unnamed contract
An Approval event from you to a contract not on Delvo's checked list.
Operator for a whole collection
An ApprovalForAll(you, operator, true) event.
Approval for one item
An ERC-721 Approval event (four topics) from you.
Funds go to a third address
A transfer out of your address to an address that is neither the target, a named contract, nor a pool proved by its factory.
An item leaves your wallet
An ERC-721 Transfer event from you.
Events and balances disagree
For each token: the sum of Transfer events for you differs from balanceOf(you) after minus before, read in the same simulated block.
Large price move
A swap moves its pool's price by 2% or more: (sqrtPrice after / sqrtPrice before)^2 − 1.
HYPE sent to a contract without calldata
value > 0, no calldata, and the target has code.
Events not decoded
An event that is not a transfer, approval or swap shape Delvo reads.
Swap in a pool Delvo cannot prove
A swap event from an address that is not a pool of a known factory (getPool returns it) or a known PoolManager.
Not enough HYPE
The node refuses the simulation because the sender holds less HYPE than the calls send. The preview adds the missing HYPE inside the simulation only and says so.
revertsThis transaction would revert. Nothing would move, but you would still pay gas.
incompleteIncomplete: some reads failed, so this preview cannot say what it did not see.
flagsRules fired. Read each one before you sign.
no-rule-firedNo rule fired on this simulation. That is not a guarantee: read what the rules do not check.
A revert or a refused balance wins over everything; then any unread input makes the result incomplete; then a stop or warning; only then “no rule fired”.
- The simulation runs on the latest block. The real transaction lands later; prices and balances can change in between.
- A contract can behave differently when it can tell it is being simulated, or at a later time or block.
- Delvo reads balances and allowances the token reports. A token can misreport them.
- Approvals you gave before this transaction are not part of this preview: see Allowances.
- Names come from a short list of contracts checked on 13 Nov 2026; an unnamed contract is not a bad one, and a named one can still be misused.