IB Option Chain

Fetch option chain data from Interactive Brokers for a specific expiration date. Handles equities/ETFs (Stock/OPT) and futures options (FOP). The asset type and exchange are resolved from IB contract details (no hardcoded symbol table): auto-detect tries a SMART stock first and falls back to a future when no stock exists (so NQ, GC, RTY resolve as futures, while AAPL resolves as a stock even though it has an obscure single-stock future). Tickers that are both a stock and a futures root (e.g. ES=Eversource, CL=Colgate) default to the equity — pass --sec-type fut to force the future.

IB Connection

TWS or IB Gateway must be running locally with API enabled:

• Paper trading — port 7497
• Live trading — port 7496
• IB_PORT env var — default port when --port is omitted (e.g. IB_PORT=4001 for a Gateway container). Precedence: --port flag > IB_PORT > built-in default. Set it in the shell or a .env file.