SPCX

Can rewrite the swap before it happens, including how much you pay.

• takes a cut of swaps
  The hook may add or remove value on every swap. Our fills for this pool come from the on-chain quoter, so whatever it takes is already in the number you see.
• sets its own fee per swap
  Dynamic-fee pool: the hook picks the LP fee at swap time. It can be 0 or 100%, and it can differ by direction, size or sender.
• gates who can add liquidity
  Usually means the hook (or its launchpad) is the sole LP — no one else can dilute or front-run the curve. It also means you cannot LP here.
• controls pool creation
  Only pools the hook agrees to can be created with it — the launchpad pattern.