If you are at all unsure, ask!
Ask the person who brings you the menu what they would recommend for someone on a gluten free diet. They may be able to point out meals that are safe for you to eat. If they are not sure, explain what you cannot eat and ask if a particular choice contains those ingredients. If you are not confident in their reply, ask if you could talk to the chef. Depending on the restaurant, the chef may come to the table to assist you.
More and more, these days I am finding that members of the restaurant staff either have celiac themselves or know someone who does. As such they are quite happy to cater for others with the condition, and they can quickly point out the dishes that you can eat safely.