This chapter examined the pivotal role of annotations within GitHub check runs. Our example highlighted how these annotations, beyond mere textual markers, significantly enhance code review processes and foster effective team collaboration. Shifting from theory, we demonstrated the practical utility of annotations. Through real-world scenarios, we showcased how they efficiently transform workflow-generated data into meaningful feedback, offering developers a powerful tool to optimize code quality seamlessly. We unraveled the process of translating build warnings into specific code annotations, enabling quicker issue identification and resolution. Our discussions further led us to an evolved version of the RichChecks action, which has been enhanced with expanded capabilities. We illustrated how integrating linting tools, notably Docker and Bicep, can write their outputs into a check run, offering a holistic view of potential code enhancements. The latter part of this chapter...