Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
v4 hook · Robinhood Chain · block 93,174,689
0x18C3…28cC
The eight checks
6 pools use this hook, the first one 12 d ago.
- 01caution
Permissions that touch your moneyThe address enables before swap returns delta, after swap returns delta. The hook is allowed to take; the next two checks measure whether it does.
- 02pass
What it takes from a swapIt takes 1% on top of the pool fee.
- 03n/a
LPs can get outClosed to outside LPs: only the hook's own liquidity is in the pool.
- 04pass
The fee is the feeA fixed fee of 0%, written in the pool key.
- 05caution
No one holds the switchOwned by 0x7d69d39542a9EaB2BB408E7A7dEd4bd9AdD4cB32. Owner-style functions: collect, setLaunchFee, setOperator, setCreator, setStartTick, transferOwnership.
- 06pass
The code cannot changeNot a proxy, no DELEGATECALL, no SELFDESTRUCT.
- 07pass
Only the PoolManager can call itEach callback refused a call that did not come from the PoolManager.
- 08pass
Track record6 pools over 12 days.
Measured at block 93,174,689. A hook with an owner or a dynamic fee can behave differently later; scan again before a large trade.
What the address allows
A v4 hook's permissions are the last fourteen bits of its address. The PoolManager calls only what they switch on.
address & 0x3fff0x28cc · 10100011001100
- bit 13Before initialize
- bit 12After initialize
- bit 11Before add liquidity
- bit 10After add liquidity
- bit 9Before remove liquidity
- bit 8After remove liquidity
- bit 7Before swap
- bit 6After swap
- bit 5Before donate
What it did to a real swap
A small swap each way and a liquidity round trip, run through the PoolManager and this hook inside a call that is never sent. The pool fee is expected; anything else missing is the hook.
WHS / GRASS
fee 0%- Swap WHS → GRASShook takes 1.00%
- Swap GRASS → WHShook takes 1%
- Add, then remove liquiditydeposit refused: HookNotAllowed
pool 0x0c379b38f44260f1d77948ab9be7f9dc47aabb3b1701ad0f5b6ccee35c0ea705
WHS / AXIE
fee 0%- Swap WHS → AXIEhook takes 1.00%
- Swap AXIE → WHShook takes 1%
- Add, then remove liquiditydeposit refused: HookNotAllowed
pool 0xa22b40597d8599064f03697bcab87600976d399dced39312ea15eb8095bd1365
Read from the bytecode
- Code size
- 17,542 bytes
- Owner
- 0x7d69d39542a9EaB2BB408E7A7dEd4bd9AdD4cB32
- Proxy
- no
- DELEGATECALL
- absent
- SELFDESTRUCT
- absent
- Outside calls
- 15
- Callbacks open to anyone
- none
Its functions, uncensored
Selectors found in the dispatcher, named from the public signature database. Red ones are what an owner usually keeps for itself.
- 0x03fd2a45 DEAD
- 0x0cfb82c0 MAX_START_TICK
- 0x1f0a3773 studioCount
- 0x21d0ee70 beforeRemoveLiquidity
- 0x259982e5 beforeAddLiquidity
- 0x28ff1d4c MAX_LAUNCH_FEE
bit 4
After donate
bit 3Before swap returns deltabit 2After swap returns deltabit 1After add returns deltabit 0After remove returns delta- Before initialize. Runs once, when a pool is created.
- Before add liquidity. Can refuse a deposit, or only let some addresses provide liquidity.
- Before swap. Runs before every swap. On a dynamic-fee pool it can set the fee each time.
- After swap. Runs after every swap.
- Before swap returns delta. Can take part of what you put into a swap, or change how much is swapped.
- After swap returns delta. Can take part of what you get out of every swap.
0x45904567
CREATOR_BPS
0x46ca626b TICK_SPACING0x497777d5 collect0x5313be2c setLaunchFee0x558a7297 setOperator0x55d73d6a launch0x575e24b4 beforeSwap0x5e3f2727 LP_FEE0x62308e85 POOL_MANAGER0x6c2bbe7e afterRemoveLiquidity0x6d70f7ae isOperator0x6fe7e6eb afterInitialize0x715018a6 renounceOwnership0x79ba5097 acceptOwnership0x85ec9bd9 setCreator0x8652edf9 poolKeyOf0x8da5cb5b owner0x91dd7346 unlockCallback0x988b1fa7 poolOf0x98aab22e startTick0x9f063efc afterAddLiquidity0xad8922b5 studio0xb47b2fb1 afterSwap0xb6a8b0fa beforeDonate0xbc234eb7 hookPermissions0xbf333f2c FEE_BPS0xc502ccb4 setStartTick0xcf3cf573 launchFee0xd92e82e4 CONFIG0xdc98354e beforeInitialize0xe138818c platformTreasury0xe1b4af69 afterDonate0xe30c3978 pendingOwner0xe81fa841 TREASURY_IMPL0xf2fde38b transferOwnership0x06fdde03 name0x095ea7b3 approve0x18160ddd totalSupply0x23b872dd transferFrom0x313ce567 decimals0x70a08231 balanceOf0x95d89b41 symbol0xa9059cbb transfer0xc50497ae SUPPLY0xdd62ed3e allowance