TOOL OPTIMIZATION CORE: ABSTRACT (PROJECT DESCRIPTION) Beyond datasets, Bridge2AI’s Data Generation Projects (DGPs) will create a rich set of software methods and tools. The Tool Optimization Core (TOC) will be a national and multi-national hub for algorithmic and methodo- logic innovation, benchmarking, standardization, optimization, and dissemination. We aspire to be a Commons that services a broad and diverse range of stakeholders: algorithm developers and users, citizen scientists, reg- ulatory bodies, and members of the public. With this overarching mission, our TOC aims to incorporate each stakeholders’ specific needs as well as merge expertise, innovation, and dissemination to enable tool optimization across the broader Bridge2AI initiative. Our Tool Optimization Core comprises five Specific Aims. First, we will support tool generalization. The TOC will serve as a Center of Excellence in benchmarking, software development, and user interface (UI) development as well as provide resources to support critical existing tools and tools generated by data generating projects (DGPs). Second, we will coordinate tool development within and beyond Bridge2AI. The TOC will coordinate benchmarking, standards-setting, and interface development for DGPs working with other NIH-funded consortia and initiatives. Third, we will benchmark and optimize tools. The TOC will identify, plan, and execute quarterly pan-Bridge2AI crowdsourced benchmarking exercises to identify and quantify best-practices while working with DGPs on a wide range of algorithms. Fourth, we will identify and fill gaps in tool development, optimization, and generalization. The TOC will create working groups across the DGPs Tool Development & Optimization Modules to identify gaps and subsequently coordinate creation of gold standard datasets and tool optimization in these spaces. Fifth, we will disseminate best practices in tool development and optimization. The TOC will create a standardized registry for sharing of tools, datasets, and benchmarking results with these resources available through programmatic and visual interfaces. These efforts will be achieved through coordination of the TOC with other BRIDGE Coordination Center Cores, particularly including the Standards Core and Skills & Workforce Development Core. Successful execution will allow the TOC to comprehensively advise DGPs, create open and coordinated tool development within and beyond Bridge2AI, develop Bridge2AI-wide benchmarking, harmonize tool development across Bridge2AI, and develop and host workshops and systematic training materials on Bridge2AI. The efforts of the TOC will support continual tool refinement and development with lasting impact for the scientific community.