Presentation given at the Ontologies4Chem Workshop 2025. Abstract:The ARC² framework (Annotated Research Context and Annotated RO-Crate) introduces a declarative, provenance-driven approach to describing research data through the processes that generate them. ARC combines a lightweight file- and folder-based scaffold for organizing data and metadata with a standards-compliant RO-Crate representation for machine-actionable publication. Building on the ISA model and Common Workflow Language, it unifies experimental and computational provenance in a consistent, semantically rich format. Through its modular design and supporting tools, ARC makes structured, FAIR, and interoperable data description accessible to researchers across disciplines.