At maximum, the Sharp-tailed Snake may grow to a length of 19 inches (47.5cm), but most adults are about 12 inches (30cm) long. Shiny reddish-brown or gray scales above and a whitish line down the side characterize C. tenuis. An alternating pattern of black, pale greenish, gray, or cream bars can be found on its belly, and its smooth scales come in 15 rows around the body. The most distinguishing characteristic of this snake is the sharp spine-like scale at the tip of its tail. Although the function of this scale is not completely understood, it is thought to be used as an anchor during struggles with its victims (Basey 1976; Leviton 1971).
About feeding habits... I have caught and studied several Sharp-Tailed Snakes, and this is what the generalized feeding habits/behaviors were. They generally eat small slugs that range in .5 inches to 1.5 inches, also on a slightly more rare occasion they will eat worms. When they try to "hunt" they first locate a animal, once that is done they hunch back and brace the sharp part of there tail into the ground. They then lunge with there tail anchoring them, and grab there victim. One of the interesting things I found about them, is they would "chew" there selected targets for up to 20 seconds before swallowing.