The field of education relies heavily on instructional coaches to build teacher capacity in the implementation of evidence-based practices (EBPs) with fidelity. Although observation tools are used to measure the fidelity of implementation by teachers, less is reported about specific behaviors demonstrated by a coach. This two-part nonexperimental study involved the use of primary and secondary data. Through this study, I sought to develop a valid and reliable coaching observation tool to analyze 36 recorded real-time coaching sessions supporting the implementation of an EBP, Targeted Reading Intervention (TRI). The tool was developed using an iterative process of initial coach interview and systematic review of the literature, review of a sample of recorded coaching sessions with the initial draft of the tool, and focus group member checking interview with coaches. Next, the tool was used to analyze a sample of recorded TRI coaching sessions. The coaches in the present study provided coaching to teachers during year 2 of a TRI multi-site randomized controlled trial study. The tool was used to identify the frequency of coaching behaviors during real-time coaching sessions. Future research may examine the technical adequacy of the tool even more rigorously. This tool may be helpful to identify coaching practices to support the implementation of EBP. Researchers using coaching to support the implementation of EBP alone, or as a component within professional development, may find this tool useful in providing them a clearer understanding of the instructional coach in building teacher capacity with the implementation fidelity of the EBP.