The FAIR-IMPACT Guidelines for recommended metadata standards for research software within the EOSC present the first proposal of the Research Software MetaData (RSMD) Guidelines, developed by Task 4.3 (T4.3), Standard metadata for research software, as part of Work Package 4, Metadata and ontologies, in the FAIR-IMPACT project. FAIR-IMPACT aims to realize a FAIR (Findable, Accessible, Interoperable, and Reusable) European Open Science Cloud (EOSC) by leveraging community guidelines and existing infrastructures in the scholarly ecosystem. The growing recognition of software's crucial role in research has led to initiatives, infrastructures and research institutions to address the challenges of software findability, accessibility, attribution and reuse. One of these initiatives, the Scholarly Infrastructures for Research Software (SIRS) Task Force (TF), identified in its report (EOSC Executive Board & EOSC Secretariat, 2020) the general need for actionable, standardized guidelines for researchers/developers that self-archive software or submit software for publication. The FAIR-IMPACT project acknowledged the rising need for establishing software metadata guidelines to effectively collect and curate metadata. In response, T4.3’s deliverable provides a comprehensive set of Research Software MetaData (RSMD) Guidelines that offer flexible and adaptable recommendations for end-users that can be used in different disciplines and different software development contexts. This deliverable summarizes a large review and analysis including: a thorough introduction of the goals, methodology and use cases; the state of the art of existing practices and guidelines and the metadata landscape. Following the first introduction and state of the art, T4.3 introduces the RSMD guidelines proposal to collect and curate research software metadata. These guidelines are directly addressed to end users, including software creators and curators in their quest to improve the FAIRness of their software. Lastly, T4.3 will continue its efforts to make the RSMD guidelines normative within the academic community. This includes engaging with stakeholders, gathering feedback, and incorporating best practices and advancements in metadata management within existing infrastructures. By establishing these guidelines as a norm, the aim is to promote widespread adoption and adherence, leading to greater standardization and harmonization of metadata practices across research domains. The ongoing commitment of T4.3 to refining and promoting the RSMD guidelines will contribute to the overall advancement of open and FAIR research practices in the research software community. The purpose of this deliverable in general and of the RSMD guidelines in particular is to provide a concrete and practical resource to support researchers in their endeavors to share and publish their research software creations.