| Field | Value |
|---|---|
| Standard | Simple Knowledge Organization System (SKOS) |
| W3C Recommendation | SKOS Reference — 18 August 2009 |
| W3C Companion Notes | SKOS Primer, SKOS Use Cases & Requirements |
| Namespace | http://www.w3.org/2004/02/skos/core# |
| RDF/Turtle Source | skos.rdf, skos.ttl |
| Authority | World Wide Web Consortium (W3C) under the Semantic Web Activity |
| npm Package | @amlhubs/skos |
| npm Version | 0.0.1 |
| Peer Dependencies | @amlhubs/rdf — RDF abstract syntax · @amlhubs/rdfs — RDF Schema vocabulary |
| License | UNLICENSED |
SKOS — the Simple Knowledge Organization System — is the World Wide Web Consortium standard for representing thesauri, taxonomies, classification schemes, subject-heading systems, and other forms of structured controlled vocabulary on the Semantic Web. The specification was issued as a W3C Recommendation on 18 August 2009 by the W3C Semantic Web Deployment Working Group. SKOS is the de-facto interoperability layer for the world's library catalogues, archive finding aids, government statistical taxonomies, museum collection vocabularies, and corporate-knowledge thesauri: every system that claims SKOS conformance can exchange its hierarchy and labels with every other SKOS-conformant system without a custom converter.
The @amlhubs/skos npm package repackages the SKOS Reference vocabulary as an extensible TypeScript metamodel surface. The package exposes the four core concept classes (skos:Concept, skos:ConceptScheme, skos:Collection, skos:OrderedCollection), the three lexical-label properties (skos:prefLabel, skos:altLabel, skos:hiddenLabel), the seven documentation properties (skos:note, skos:scopeNote, skos:definition, skos:example, skos:historyNote, skos:editorialNote, skos:changeNote), the five semantic-relation properties (skos:broader, skos:narrower, skos:related, skos:broaderTransitive, skos:narrowerTransitive), the five mapping properties (skos:exactMatch, skos:closeMatch, skos:broadMatch, skos:narrowMatch, skos:relatedMatch), the two collection properties (skos:member, skos:memberList), the three concept-scheme properties (skos:inScheme, skos:hasTopConcept, skos:topConceptOf), and the notation property (skos:notation). Each surface element will carry a JSDoc header citing the precise SKOS Reference section that defines it, and the package depends on @amlhubs/rdf and @amlhubs/rdfs so that every SKOS instance is a typed RDFS instance by construction.
SKOS is intentionally a simple model: it offers a small, opinionated vocabulary for the structural patterns that knowledge-organization systems share, while explicitly leaving richer constructs (concept-relation typing, faceted classification, post-coordination logic) to companion standards. The library and information-science community separately maintains ISO 25964 — Information and documentation: Thesauri and interoperability with other vocabularies — which targets the same interoperability problem from a thesaurus-management standpoint. This package implements SKOS strictly as defined by the W3C Recommendation; ISO 25964 alignment is a non-goal of the typed surface and is mentioned here only for comparison.
Adopting SKOS through a typed package produces an immediate library- and archive-ecosystem interoperability dividend. Every major bibliographic and archival platform — Library of Congress Subject Headings, AGROVOC, EuroVoc, Getty AAT, MeSH, UNESCO Thesaurus, DBpedia, Wikidata, and the European Open Data Portal — publishes its taxonomies as SKOS RDF. A controlled vocabulary expressed against the metaclasses @amlhubs/skos exports is, by construction, importable into every one of those platforms without a custom mapping layer. Ventures building knowledge graphs, content-classification engines, recommendation systems, or retrieval-augmented agents amortize what would otherwise be a per-vocabulary integration cost to zero.
W3C Recommendation status turns internal taxonomy decisions into citable, durable artifacts. The SKOS Reference is referenced in government open-data mandates, in DCAT data-catalogue publishing pipelines, in European Union semantic-interoperability frameworks, and in academic information-architecture standards. A vocabulary published against this typed surface can be cited directly to W3C, and a downstream auditor evaluating data-quality or interoperability claims sees a one-to-one correspondence between the cited specification section and the executable artifact.
The third lever is agentic content-classification leverage. Ageni's content, copy-generation, and retrieval pipelines treat domain taxonomies as the deterministic substrate over which large-language-model reasoning operates. When an agent classifies a product, motivation, audience segment, or pitch ingredient against a SKOS Concept tree, the typed surface provided by this package gives the TypeScript compiler the same well-formedness guarantees the W3C Recommendation provides at the data layer: a hallucinated concept reference (one not present in the Concept hierarchy, one violating skos:broader/skos:narrower invariants, one introducing a forbidden cycle) is caught at compile time. The agent's classification surface is reduced from the open set of possible English labels to the closed set of typed SKOS concept compositions, and every classification trace becomes auditable against the upstream W3C specification.
The fourth lever is compounding reuse across the amlhubs metamodel stack. SKOS sits on top of RDFS, which sits on top of RDF; this package depends on both. Downstream metamodels that need a controlled-vocabulary backbone — DCAT for data-catalogue publishing, FOAF for social-graph vocabularies, OWL for ontology engineering, FIBO for financial taxonomies — all reuse SKOS as the canonical taxonomy layer. Every ageni venture that publishes a controlled vocabulary (lesvolsarabais.ca's destination taxonomy, illummaa.com's product-feature taxonomy, dealsempire's pitch-strategy taxonomy, the ageni.io marketplace's capability taxonomy) consumes this package directly. The engineering investment that produces @amlhubs/skos is amortized across every venture that ever extends it.
The package exports the SKOS Reference vocabulary grouped by structural role. The complete enumeration lives in skos.ts; the table below summarizes the groups and cites the authoritative section.
| SKOS Surface | §Section | Members |
|---|---|---|
| Concept classes | §3 / §4 / §9 | skos:Concept, skos:ConceptScheme, skos:Collection, skos:OrderedCollection |
| Lexical-label properties | §5.3 | skos:prefLabel, skos:altLabel, skos:hiddenLabel |
| Documentation properties | §7 | skos:note, skos:scopeNote, skos:definition, skos:example, skos:historyNote, skos:editorialNote, skos:changeNote |
| Semantic-relation properties | §8 | skos:broader, skos:narrower, skos:related, skos:broaderTransitive, skos:narrowerTransitive |
| Mapping properties | §10 | skos:exactMatch, skos:closeMatch, skos:broadMatch, skos:narrowMatch, skos:relatedMatch |
| Collection properties | §9 | skos:member, skos:memberList |
| Concept-scheme properties | §4 | skos:inScheme, skos:hasTopConcept, skos:topConceptOf |
| Notation property | §6 | skos:notation |
The full list and the JSDoc headers citing each §-section live at skos.ts.
@amlhubs/skos is a downstream specialization of RDFS. It depends on @amlhubs/rdf and @amlhubs/rdfs and is depended on by every downstream amlhubs metamodel that surfaces a controlled vocabulary.
@amlhubs/rdf (RDF abstract syntax)
▲
│ peerDependency
└── @amlhubs/rdfs (RDF Schema vocabulary)
▲
│ peerDependency
└── @amlhubs/skos (this package)
npm install @amlhubs/skos @amlhubs/rdfs @amlhubs/rdfConcrete metaclass declarations and SKOS-specific helpers will arrive in subsequent versions of this package. The current 0.0.1 release is a banner-and-spec-corpus scaffold: it pins the W3C Recommendation, the namespace, the upstream peer dependencies, and the metaclass enumeration skos.ts will surface.
- SKOS Reference — W3C Recommendation, 18 August 2009
- SKOS Primer — W3C Working Group Note
- SKOS Use Cases and Requirements — W3C Working Group Note
- SKOS Reference HTML — alternate W3C location
- SKOS namespace document
- skos.rdf — authoritative RDF/XML source
- skos.ttl — authoritative Turtle source
- W3C Semantic Web Activity
- For a comparison-only reference to the parallel ISO 25964 thesaurus standard, see ISO 25964 — Thesauri and interoperability with other vocabularies. Note that this package implements SKOS only, as defined by the W3C Recommendation cited above; ISO 25964 alignment is a non-goal of this typed surface.
| Version | Date | Change Summary |
|---|---|---|
| 0.0.1 | initial scaffold | W3C SKOS Reference banner-only metaclass enumeration; peer-depends on @amlhubs/rdf and @amlhubs/rdfs; spec corpus and reference-implementation corpora bundled. |
UNLICENSED — restricted npm access under @amlhubs scope at npm.pkg.github.com.