Metadata ("data about data") enhances findability, machine processing, and interoperability.

• Administrative Metadata: Bibliographic details (authors, ORCID, DOI), funding references, and licensing terms.

• Technical/Metrology Metadata: Essential for traceability. Include methodology, instrument specifications, environmental conditions, and Calibration and Measurement Capability (CMC) coverage (a valid CMC code linking to a regional metrology organization).