Pick a ceiling. Read what it costs you.
A guard is a Uniswap v4 hook and a single number: the most its surcharge may ever charge. Everything else follows from that, so rather than describe the presets in prose, every card below is run through the same solver the proof table uses and prints what it actually recovers.
No guard recovers a split in full, at any setting.
The ceiling exists so the guard can never become the extraction it is meant to prevent. Raising it to make a table look better is the change we are not going to make — uncapped, the surcharge bricks the pool on a large action. The cost of that choice is the number in the “of a split” pill on every card.
Each guard states its limits on its own card.
A ceiling is not a price floor
The surcharge changes who captures a discontinuity. It does not stop the discontinuity happening, and it does not hold the pool's price up.
A guarded pool is still an equity position
Siren defends against the accounting discontinuity. It does nothing about the underlying going down, and nothing about you holding the wrong stock.
An unarmed guard is not a guard
Every figure on these cards assumes the pre-action window fired. If no keeper read effectiveAt(), the guard is inert and the LP eats the unguarded column.
The dial is stated. So is what it fails to cover.
Read the proof table before you trust any number on this page.