Execute N minutes after the session open or before the session close, on every session (anchor:open|close, offset_minutes: int >= 0 after the open, <= 0 before the close; -5 with close = five minutes before the close, half-days resolved against that date's real close). Schedules the decision at that instant and fills from the 1-minute execution clock, on ANY timeframe. The rule is evaluated ONLY then and places a market order, so other conditions on it are sampled at that moment; never put a protective exit on one. Equity only: refused for crypto (24h sessions have no open or close; use at_time). Only an entry or an exit trigger, alone or under all_of.