Option chain

Originator and date

AlertDesk's maker, 10/11/2026: each ticker page shows the option chain, from the Yahoo chain data AlertDesk already reads for the evening marks, with a way to put a contract straight into Add a trade.

Industry sources read

Yahoo Finance's option chains (finance.yahoo.com), read through the open-source yfinance library (github.com/ranaroussi/yfinance), the same way AlertDesk reads its evening marks. Yahoo's quotes are delayed (about 15 minutes); its terms allow personal use: legal.yahoo.com/us/en/yahoo/terms/otos/index.html. No account is needed to see chains. OptionStrat (optionstrat.com) and Webull (webull.com) show more -- Greeks, implied volatility, strategy builders -- if wanted.

What prompted it

Trading from a service's recs: seeing the contracts a service names, and nearby strikes, beside your own positions without leaving AlertDesk.

What we changed and why

Nothing in Yahoo's numbers. AlertDesk shows one expiry at a time, nearest first; the strikes nearest the last price (all on request); calls left, puts right; the mid worked out as halfway between bid and ask (none when either is zero), the same rule as the marks. Fetched only when the user opens it and kept for the session -- never in a job -- so the page stays within its one-second budget. Information, not advice.

Our own evidence

The tests replay a recorded chain through the same Yahoo layer (`tests/test_option_chain.py`): centring, both sides, the mid, the session cache (one fetch per expiry), "Use this contract" filling Add a trade, and the plain words when there's no source or Yahoo doesn't answer. First used live in 0.2.9.