The purpose of this Milestone is to initiate the prototyping phase, embodying FAIR-IMPACT’s approach to implementing the principles outlined in the initial version of the “Guidelines for repositories and registries on exposing repository trustworthiness status and FAIR data assessments outcomes” (Milestone 5.2). The proposed standards and technology stack are based on insights gathered through the activities in the earlier project FAIRsFAIR “Fostering FAIR Data Practices In Europe” and cross-work package collaboration and exchange among the FAIR-IMPACT project partners. This application of this stack is aimed at complementing the guidelines' technology and tool-agnostic character by establishing an initial linking and information structure for the prototype to be developed. It is intended to bridge repositories with registries and discovery services, thereby facilitating the better exposure and discovery of repository information. The registry role within the prototype will be covered by re3data - registry of research data repositories. In addition, it will enable the provision of information on the object level as well as quality measures due to the extensibility of the chosen technology stack. This work will serve as the foundation for the development of future guideline versions. Suggestions collected from the community will be used for revising, extending, and refining the transparent exposure of repository information and its support in registries like re3data as well as other services, such as F-UJI and CoreTrustSeal. Thus the approach is similar to the development of the guidelines and ensures that not only the prototype but also guidelines themselves remain responsive to the needs and insights of stakeholders.