What a good website does.
A platform-agnostic specification of the technical features every
decent website should have — from <title>
to /.well-known/security.txt,
from WCAG contrast to llms.txt.
Written for humans and agents.
Categories
Ten areas, mapped to widely-accepted standards.
-
The HTML, head, and document basics every page needs.
-
Search visibility — robots.txt, sitemaps, canonicals, structured data.
-
WCAG-aligned rules so people of all abilities can use the site.
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Headers, transport, and policies that keep visitors safe.
-
Standard, agreed-upon paths under /.well-known/.
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Things that make a site legible to AI agents and crawlers.
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Core Web Vitals, caching, images, fonts, network behaviour.
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Consent, signals, and respecting visitor choice.
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Graceful failure — error pages, offline, redirects.
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Language, locale, direction, and translated content.
Standards, not opinions
Each topic links back to the source standard — WHATWG, W3C, IETF RFCs, WCAG, MDN, and the organisations defining the modern web.
Platform agnostic
Whether you ship WordPress, Drupal, TYPO3, Next.js, Astro, Hugo, a Django app, or plain HTML, the spec is the spec. Implementation hints follow it, not the other way round.
Built in the open
Every page has an Edit on GitHub link. PRs welcome. Sources credited on every page.
Let your agent query the spec.
The whole spec is available as an open MCP server — read-only, no auth — plus a published Agent Skill that teaches any compatible agent when and how to use it. Per-page Markdown is available via /llms.txt and Accept: text/markdown on any spec URL.
{
"mcpServers": {
"specification-website": {
"transport": "http",
"url": "https://mcp.specification.website/mcp"
}
}
}How to use this site
- 01
Audit
Run through the checklist. Each item is a “does the site do this — yes or no.”
- 02
Learn
Click into any item for what it is, why it matters, and how to implement it.
- 03
Improve
Found a gap, a stale fact, or a missing topic? Open a PR. Sources required.