Fiscal Geometry is presented as a neutral analytical interface designed to provide structural visibility prior to analysis, interpretation, or evaluation. Rather than advancing normative claims or policy prescriptions, this technical note specifies an upstream coordination layer that renders fiscal rules, capital flows, and institutional interactions as coordinate-based objects on an X–Y plane. The document clarifies the role of Fiscal Geometry as an interface that sits before domain-specific modeling, index construction, or expert judgment. It does not replace professional analysis, accounting practice, or institutional decision-making. Instead, it provides a shared structural rendering that enables analysts, researchers, and practitioners to observe patterns, clusters, and boundary interactions in complex fiscal environments using publicly available data. This technical note is intended as an interface-level specification for use across multiple institutional contexts, including policy analysis, professional services, family offices, and philanthropic organizations. Downstream data collection, cleaning, interpretation, and application remain the responsibility of users and domain specialists. By maintaining neutrality and reusability, Fiscal Geometry functions as a foundational analytical interface that supports interdisciplinary dialogue and sectoral application without imposing interpretive or normative positions.