How are options exercised?
There is no manual exercise step. Contracts are settled automatically in cash at expiry (08:00 UTC). See Settlement & Expiry.Are trigger orders or leverage supported?
No. Only limit and market orders are supported, and leverage / margin-mode updates do not apply. See Order Lifecycle.Where do mark price, IV, and Greeks come from?
They are published continuously on the Contracts Stream and derived from the Black-76 model. To preview values for a specific order, use the Get Contract Pricing endpoint. See Pricing & Greeks.How do I list what’s currently tradable?
Subscribe to the Contracts Stream, or use the REST Get Expirations and Get Contracts endpoints.How do I verify an order and safely retry?
If a request times out or you miss an acknowledgment, do not blindly resubmit. Check the order’s status (for example via your open orders) after a short wait, and only retry if it is confirmed missing. Use a uniqueclientRequestId per request so you can correlate acknowledgment, confirmation, fills, and
errors.