Returns the complete options chain including all expirations and contracts,
with bid, ask, mid prices, greeks, and Helium's proprietary model values
(helium_theo, helium_pitm, should_i_buy, should_i_sell, terminal_buy_pl,
terminal_sell_pl, etc.) baked into each contract.
Returns:
- symbol, date, data_source ('recent' or 's3')
- num_expirations: number of distinct expiration dates
- total_contracts: total number of option contracts
- option_chain: dict keyed by expiration index, each value is a list of option contracts
Each contract includes fields like: putCall, symbol, description, bid, ask, mark,
mid_price, strikePrice, expirationDate, daysToExpiration, delta, gamma, theta, vega,
impliedVolatility, openInterest, volume, helium_theo, helium_pitm, should_i_buy,
should_i_sell, terminal_buy_pl, terminal_sell_pl, and more.
Args:
symbol: Ticker symbol, e.g. 'AAPL', 'TSLA', 'SPY'.
date: Date in YYYY-MM-DD format, e.g. '2026-04-10'.