The high demand for mental health treatment combined with a shortage of mental health specialists leads to long waiting times for affected individuals. To counteract the lack of necessary resources, the focus has increasingly shifted to internet-based psychotherapy and to the use of conversational agents (CAs) in this context. This scoping review aims to identify and analyze intervention methods from cognitive behavioral therapy delivered by CAs. A literature search is conducted, including research published between 2015 and 2023, to identify existing research on CA-based cognitive behavioral therapy as well as gaps in the current research landscape. Following the updated PRISMA guidelines for reporting systematic reviews, 241 publications are identified and reduced to a result set of 41 based on a rigorous screening process. In those, 32 individual tools are found and analyzed regarding used interventions, targeted conditions, and modality. The results show that chatbots are mostly used in existing approaches. The most implemented interventions include psychoeducation, cognitive restructuring, behavioral activation, mindfulness exercises, and monitoring. Several shortcomings in the research field are identified that should be addressed in future studies, including the comparison of different kinds of CAs, clinical trials with active control groups to investigate the efficacy for different mental health conditions, and the isolated examination of chosen intervention methods delivered via CAs.