generated: '2026-09-07'
method: searched
source: >-
  registry.npmjs.org metadata endpoints, https://jigsaw.w3.org/css-validator/DOWNLOAD.html
  and the GitHub releases API for w3c/css-validator
note: >-
  CSS is a specification, not a product, so there is no client SDK for "the CSS API" and
  none is claimed here. What the W3C does publish are (a) machine-readable extracts of the
  CSS specifications, shipped to npm from the w3c/webref and w3c/browser-specs repositories,
  and (b) the CSS Validator itself, distributed as a runnable jar. Only packages published
  from a repository in the w3c GitHub organization are marked official.
packages:
  - name: '@webref/css'
    registry: npm
    url: https://www.npmjs.com/package/@webref/css
    repository: https://github.com/w3c/webref
    language: javascript
    official: true
    kind: data
    version: 8.7.4
    published: '2026-09-04'
    license: MIT
    description: >-
      CSS definitions of the web platform — per-specification JSON extracts of every
      property, at-rule, descriptor, selector and value definition, generated from the CSS
      specifications by the W3C webref tooling.
  - name: '@webref/idl'
    registry: npm
    url: https://www.npmjs.com/package/@webref/idl
    repository: https://github.com/w3c/webref
    language: javascript
    official: true
    kind: data
    version: 3.83.1
    published: '2026-09-04'
    license: MIT
    description: >-
      Web IDL definitions of the web platform, including the CSSOM and CSS Houdini
      interfaces (CSSStyleDeclaration, CSSStyleSheet, CSS Typed OM, Paint/Layout Worklet).
  - name: '@webref/elements'
    registry: npm
    url: https://www.npmjs.com/package/@webref/elements
    repository: https://github.com/w3c/webref
    language: javascript
    official: true
    kind: data
    version: 2.8.0
    published: '2026-08-26'
    license: MIT
    description: Markup elements of the web platform and their associated Web IDL interfaces.
  - name: web-specs
    registry: npm
    url: https://www.npmjs.com/package/web-specs
    repository: https://github.com/w3c/browser-specs
    language: javascript
    official: true
    kind: data
    version: 4.11.0
    published: '2026-09-02'
    license: CC0-1.0
    description: >-
      Curated list of technical web specifications, including every CSS module, with its
      series, level, maturity and canonical URLs.
  - name: browser-specs
    registry: npm
    url: https://www.npmjs.com/package/browser-specs
    repository: https://github.com/w3c/browser-specs
    language: javascript
    official: true
    kind: data
    version: 5.3.0
    published: '2026-06-19'
    license: CC0-1.0
    description: >-
      The browser-implemented subset of web-specs. Last published 2026-06-19, older than
      web-specs; w3c/browser-specs treats web-specs as the primary distribution.
  - name: css-validator.jar
    registry: cdn
    url: https://github.com/w3c/css-validator/releases/latest/download/css-validator.jar
    repository: https://github.com/w3c/css-validator
    language: java
    official: true
    kind: application
    version: cssval-20250226
    published: '2025-02-26'
    description: >-
      The W3C CSS Validation Service as a runnable jar — the same code behind
      jigsaw.w3.org/css-validator, usable as a command line tool
      (java -jar css-validator.jar <url>) or deployed as a war.
    note: >-
      Distributed as a GitHub release asset, not through a package registry, so there is no
      registry metadata endpoint. Version and date read from the w3c/css-validator releases
      API. The DOWNLOAD page links the floating "releases/latest" URL, so a consumer
      following that link cannot tell which build they received.
not_published:
  - registry: maven-central
    note: >-
      No org.w3c css-validator coordinate found; the jar is a GitHub release asset only.
  - registry: pypi
    note: No first-party W3C CSS package found.
  - registry: rubygems
    note: No first-party W3C CSS package found.
excluded:
  - name: mdn-data
    reason: >-
      Machine-readable CSS data, but published by Mozilla (mdn/data), not by the W3C CSS
      Working Group. Not first-party to this record.
  - name: css-tree / postcss / stylelint / @csstools/*
    reason: >-
      Third-party CSS parsers and tooling. Real and widely used, but not published by the
      W3C, so they are not this provider's packages.