Stable string-literal code for programmatic dispatch.
OptionalcolumnOptional 1-based source column for the offending node.
OptionaldetailOptional structured detail for callers that want to render rich UI.
OptionalfacetOriginating facet type when the issue is tied to a specific facet.
OptionallineOptional 1-based source line of the offending node, when the parser
exposes it. Present mainly for E_PARSE_* issues.
Human-readable message. Localised via the translator if one is provided.
XPath-ish path into the document (e.g., specifications[0].applicability.facets[1]).
Severity bucket. error issues fail the audit; warning/info do not.
A single audit finding.