Agnes built a monastery and friary complex attached to the hospital. It housed the Franciscan friars and the Poor Clare nuns who worked at the hospital. This religious complex was one of the first Gothic buildings in Prague. In 1235, Agnes gave the property of the Teutonic Knights in Bohemia to the hospital. She herself became a member of the Franciscan Poor Clares in 1236. As a nun, she cooked for and mended the clothes of lepers and paupers, even after becoming abbess of the Prague Clares the following year. As can be seen in their correspondence, Clare wrote with deep maternal feelings toward Agnes, though they never met.