Ask any data vendor for a gamma profile and you get one: a set of strikes and a number at each. It is a photograph. It tells you where positioning sits right now and nothing at all about whether it is building or draining.
Why the direction matters
A wall at a strike with a large value means one thing if it has been there all week and something quite different if it appeared in the last ninety minutes. The first is settled positioning that price has already traded around. The second is somebody arriving, and arriving positions get hedged.
The same applies to the flip. A flip sitting at a level is a boundary. A flip that has walked steadily upward all session is a market being repriced, and the path is the information.
You cannot reconstruct it later
This is the part people underestimate. Derivative positioning is computed from a book that no longer exists once it has changed. If nobody recorded the profile at eleven this morning, that reading is gone. It is not in an archive somewhere waiting to be bought; it was never written down.
Which means a vendor who has been storing snapshots for two years holds something a better-funded competitor cannot buy or reproduce. The only way to have that history is to have started.
What to ask for
When evaluating a feed, ask two things. Does it expose the session history as well as the current state? And how far back does that history go? A live number with no past is half a product, and the half it is missing is the half that answers whether this is new.