Teaism is a restaurant that serves simple dishes from Japan, Thailand, and India, also offering a wide range of traditional teas. While they are not an exclusively gluten free restaurant, they are very transparent about their ingredients and dishes. Their dietary information document can be viewed here: https://www.teaism.com/images/restaurant/diet_concern/39_1405698078_lpdietaryinfo0714.pdf
They cannot guarantee that cross contamination won't occur, and dishes should be confirmed gluten free with your server when ordering. On the dietary information document they list the specific menu items, using a simple "Y" or "N" to signify that "yes, it's gluten free" or "no, it's not gluten free," respectively. Some items like burgers or salads have special instructions like removing the bun or asking for no sauce.