Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
v4 hook · Robinhood Chain · block 93,031,377
0xCD9D…68cc
The eight checks
12 pools use this hook, the first one 110 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 0.20% on top of the pool fee.
- 03pass
LPs can get outLiquidity added and removed in the same block came back whole.
- 04caution
The fee is the feeIts pools use a dynamic fee that the hook sets before every swap. It stands at 1% now and can change.
- 05pass
No one holds the switchNo owner and no admin functions found.
- 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 record12 pools over 109 days.
Measured at block 93,031,377. 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.
T93 / WETH
fee dynamic, now 1%- Swap T93 → WETHhook takes 0.20%
- Swap WETH → T93hook takes 0.20%
- Add, then remove liquiditycame back whole
pool 0x3a75225ac50e2664859f26b130321aff94107dbef642a3b0f1aaf654d47060af
WETH / 99
fee dynamic, now 1%- Swap WETH → 99hook takes 0.20%
- Swap 99 → WETHhook takes 0.20%
- Add, then remove liquiditycame back whole
pool 0xe2fbb71b67f8927e8070bbd8550d0d03995752aedd60e45a1cba3a7a01242b34
Read from the bytecode
- Code size
- 16,517 bytes
- Owner
- none found
- Proxy
- no
- DELEGATECALL
- absent
- SELFDESTRUCT
- absent
- Outside calls
- 16
- 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.
- 0x015e3c29 initializeMevModule
- 0x01ffc9a7 supportsInterface
- 0x21d0ee70 beforeRemoveLiquidity
- 0x259982e5 beforeAddLiquidity
- 0x2b887e0f mevModuleEnabled
- 0x334e8367
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.
PROTOCOL_FEE_NUMERATOR
0x3fc48eba MAX_LP_FEE0x3fc8cef3 weth0x4468979e locker0x4c2b2876 initializePoolOpen0x4eb5313d poolExtensionSetup0x564d49e7 initializePool0x575e24b4 beforeSwap0x58f8cd54 mevModuleOperational0x6c2bbe7e afterRemoveLiquidity0x6fe7e6eb afterInitialize0x7f5464f4 mevModuleSetFee0x91b9b827 PROTOCOL0x949d32e0 MAX_MEV_LP_FEE0x9f063efc afterAddLiquidity0xac3e6ec9 poolExtension0xb0e21e8a protocolFee0xb47b2fb1 afterSwap0xb6a8b0fa beforeDonate0xbdf22863 mevModule0xc2527427 liquidIsToken00xc37fb4da poolExtensionAllowlist0xc45a0155 unknown0xc4e833ce getHookPermissions0xccc8dc43 MAX_MEV_MODULE_DELAY0xd73792a9 FEE_DENOMINATOR0xdc4c90d3 poolManager0xdc98354e beforeInitialize0xe1b4af69 afterDonate0xe1f6e19e liquidFee0xe98a4297 _runPoolExtensionHelper0xee4d96cf poolCreationTimestamp0xf732b64e pairedFee