Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
v4 hook · Robinhood Chain · block 92,922,636
0xCf57…78CC
The eight checks
55 pools use this hook, the first one 55 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 swapA swap through it pays the pool fee and nothing else.
- 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 0% now and can change.
- 05caution
No one holds the switchNo owner() but it has blockedBy.
- 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 record55 pools over 55 days.
Measured at block 92,922,636. 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 & 0x3fff0x38cc · 11100011001100
- 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.
SPY / SPY
fee dynamic, now 0%- Swap SPY → SPYnothing taken
- Swap SPY → SPYno liquidity above the price
- Add, then remove liquiditycame back whole
pool 0x455c8018741182531ae58ec834dd8b652546a6be049e00f5a1aad9d142a23428
ETH / SPRM
fee dynamic, now 0%- Swap ETH → SPRMnothing taken
- Swap SPRM → ETHnothing taken
- Add, then remove liquiditydeposit refused: NotPositionManager
pool 0xae8a223dfa6baf5fd36ea38dd07177744f1c22ce6c5c3d4b74a15491cdcb2d0e
Read from the bytecode
- Code size
- 23,400 bytes
- Owner
- none found
- Proxy
- no
- DELEGATECALL
- absent
- SELFDESTRUCT
- absent
- Outside calls
- 3
- 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.
- 0xdcf6836b quoteIsCurrency0
- 0xe1b4af69 afterDonate
- 0xf08cdfa2 liquidityAccessOf
- 0xf62983f0 rulesOf
- 0xc45a0155 unknown
- 0xc4e833ce getHookPermissions
- 0xdc4c90d3 poolManager
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.
- After initialize. Runs once, right after 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.