Execution runs entirely through the Alpaca CLI — the tool Alpaca describes
as designed for AI agents, scripts and automation pipelines. Every order is
submitted twice. Once with --dry-run, which renders the exact
request body without sending it. Then again, as the identical command, for real.
That is what lets the interface claim a position was covered before
it existed, rather than after. Each structure carries its own receipt, and
the receipt is the command.
alpaca order submit
--order-class mleg
--qty 5
--type limit
--limit-price 0.53
--client-order-id vig-3f9a1c22
--legs [
{"symbol":"SPY260903P00751000","side":"sell",…},
{"symbol":"SPY260903P00746000","side":"buy", …},
{"symbol":"SPY260903C00769000","side":"sell",…},
{"symbol":"SPY260903C00774000","side":"buy", …}
]