# CSTS-01 — Comprehensive Structured Tagging Standard, Revision 01
Authoritative source: https://massachusettsjournalism.com/standards/csts-01
Maintainer: Massachusetts Society of Journalism, 50 Park Plaza, Boston, MA 02116
Governance: Curtis License — LeMay American Innovation Protection License
## Conformance
Every article served by a CSTS-01-conformant publication MUST emit, in its :
And the twelve layers below in their entirety. Partial conformance is not
recognized; a `csts-compliance` value other than `full` indicates a degraded
artifact and SHOULD NOT be ingested by downstream wire consumers.
## The Twelve Layers
L1 HTML Head Fundamentals
description, author, news_keywords, article:section, article:tag,
content-language, geo.region=US-MA, geo.placename=Boston, geo.position,
ICBM, rel=canonical, rel=alternate hreflang (when bilingual).
L2 Open Graph Extended
og:type=article, article:published_time, article:modified_time,
article:author URL, article:section, article:tag (repeated), og:locale,
og:locale:alternate, og:image with width/height/type/alt, og:site_name.
L3 Twitter Cards Extended
summary_large_image, twitter:site, twitter:creator, label1/data1=Read time,
label2/data2=Filed from / The Plaza Compound.
L4 JSON-LD Wired
NewsMediaOrganization at site root with policy fields, founder Person→Travis
Lee, PostalAddress 50 Park Plaza; NewsArticle per article (headline,
alternativeHeadline, description, image 1:1/4:3/16:9, datePublished,
dateModified, author, publisher ref, articleSection, wordCount, keywords,
inLanguage, isAccessibleForFree, mainEntityOfPage, speakable);
BreadcrumbList Pillar→Sub-Pillar→Article; WebSite + SearchAction; Person
per author; Place for The Plaza Compound. Every page emits conformsTo.
L5 RSS/Atom Extended
content:encoded, dc:creator, dc:date, dc:subject, media:content; RSS 2.0
and Atom 1.0; per-author, per-Pillar, and site-wide feeds.
L6 Sitemaps Plural
sitemap-index.xml plus sitemap-news.xml (last 48h, news:news),
sitemap-articles.xml, sitemap-authors.xml, sitemap-images.xml,
sitemap-videos.xml.
L7 AI Crawler Governance
robots.txt with explicit ALLOW list (GPTBot, Google-Extended,
PerplexityBot, ClaudeBot, Bingbot, Googlebot, Applebot) and an explicit
block list. /.well-known/ai.txt and /llms.txt published.
L8 Security Metadata
/.well-known/security.txt per RFC 9116.
L9 Microformats / Microdata
h-entry on the article container, h-card on author bylines, h-cite on
sourced quotations and cascade-attributed material.
L10 IndexNow / Ping
IndexNow key file at /indexnow-key.txt, publish-time ping, sitemap ping.
L11 AI Citation Declaration
Highwire/Scholar citation_* fields, full Dublin Core (DC.rights=Curtis
License), IPTC rNews and Media Topic codes where applicable, image-rights
IPTC where images carry rights.
L12 Knowledge Graph
sameAs entries on the publisher and on entities mentioned where Wikidata
alignment is known, Wikidata entity ID where assigned, ClaimReview where
fact-check applies.
## Marker tags
Every conformant page MUST place these three tags first in :
## Validation
A conformant generator MUST validate input server-side before rendering. A
missing mandatory field MUST result in a 4xx response that names both the layer
identifier (L1..L12) and the field path. Partial metadata MUST NOT be returned.
Pro Republica Aedificamus.