Api V2 Gex Regime-Series Get

The Gamma Shift read at every 5-minute bar of a session.

Where /api/gex/regime-shift answers "how did dealer gamma change between these two moments" as a single card, this is the same maths as a line — so structure can sit on the same timeline as /api/flow/hedging and be read against it. Flow says how hard the tape is pushing; this says whether the book absorbs or amplifies it.

Two lenses per bar. anchored_* is versus the session's first bar ("changed today"), the counterpart of the flow panel's cumulative curve. rolling_* is versus rolling_bars bars back ("changing right now"), the counterpart of the rate line and the one to read beside a flip. They do not sum: both weight strikes by proximity to each bar's OWN spot, so the kernel re-centres every bar.

Positive stability means more long gamma near spot — dealers hedge against moves, so the tape pins. Negative means the book has turned accelerant. Positive lean means the change is supportive; negative means capping.

Scores are RAW dollar-GEX; normalising against a trailing distribution of sessions is /api/gex/regime-history's job.

Served from a table the Analytics Engine materialises one bar at a time. Computing it on read would mean diffing two ~1500-row chains per bar per viewer per poll — the shape that took the strike-profile timeseries down in Aug 2026 — so a miss returns empty rather than falling back to compute.

Each bar also carries the spot-to-flip cushion: how much room price has before the gamma regime itself changes. The flip level and the typical 30-minute move are stored; distance, direction, the rolling rate and the SECURE / NORMAL / THIN / CROSSING label are derived here, so retuning a threshold reclassifies history instead of leaving old bars labelled by a rule that is no longer live. The label is never computed from raw points, because ten points is a crossing risk on SPX and a comfortable cushion on SPY: it grades the cushion against the typical 30-minute realized move (cushion_basis='move_30m'), and falls back to a fraction of spot, which has no NORMAL band, only where no move was stored ('spot_fraction'). cushion_state of NO_FLIP means the gamma profile had no zero crossing at all, which is a different statement from a distant one.

Same session resolution as /api/flow/hedging, so the two cover identical bars. Rows newest → oldest. Unknown symbols 404; a session with nothing written yet returns an empty bars list.