specification.website valid

Automatically discovered from public files. Ownership management is optional. Inclusion does not imply endorsement or publisher participation.

Manage this listing — optional · Visit publisher ↗

Claim my listing on Agent Web Map for specification.website:
1. POST https://agentwebmap.com/v1/sites/specification.website/claims and keep claim_id and claim_secret private.
2. Publish the proof: add the line "AgentWebMap ownership: <token>" (token from step 1) to https://specification.website/llms.txt, or use the DNS, meta-tag or well-known method the response describes.
3. POST https://agentwebmap.com/v1/sites/specification.website/verify with {"claim_id": "...", "claim_secret": "..."}.
4. Save the api_key from the answer; it manages the listing (PATCH https://agentwebmap.com/v1/sites/specification.website).
MCP equivalent: tools begin_ownership_claim, then verify_domain, at https://agentwebmap.com/mcp. Docs: https://agentwebmap.com/docs#verify

Corrections or removal requests: contact the directory. Ownership management is optional.

The Website Specification

A platform-agnostic, full specification of the technical features a good website should have. Built in the open under an MIT licence.

Their llms.txt

The beginning of the file, from our validated copy saved 2026-10-21T00:36:55.026Z. Cached copy · Source on specification.website

# The Website Specification

> A platform-agnostic, full specification of the technical features a good website should have. Built in the open under an MIT licence.

This is the llms.txt index for https://specification.website. The site is a platform-agnostic specification of the technical features a good website should have. It covers HTML foundations, SEO, accessibility, security, well-known URIs, agent readiness, performance, privacy, resilience, and internationalisation.

Every individual spec page is available as raw Markdown two ways:
  1. Append `.md` to any spec URL — e.g. https://specification.website/spec/security/content-security-policy.md
  2. Send `Accept: text/markdown` to the canonical (slash-terminated) URL — the same page returns Markdown with `Content-Location` pointing at the .md path and `Vary: Accept` set for caches.

For the full content of every spec page concatenated into one file, see https://specification.website/llms-full.txt.

For richer access, two named surfaces are available:
  - MCP server at `https://mcp.specification.website/mcp` — stateless Streamable HTTP, no auth, with `search`, `list_topics`, `get_topic`, `get_checklist`, and `audit_url` tools. Server card: https://specification.website/.well-known/mcp/server-card.json.
  - Agent Skill at https://specification.website/.well-known/agent-skills/specification-website/SKILL.md — discoverable via https://specification.website/.well-known/agent-skills/index.json. Teaches a compatible agent when and how to query the spec.

Pairs well with the MDN MCP server (https://mcp.mdn.mozilla.net/). This spec tells you what a good site should do and whether it is required; the MDN MCP tells you how a web feature works and whether it is Baseline / widely supported. Use this spec to decide what to check, then MDN for implementation and browser-support detail.

## Foundations

The HTML, head, and document basics every page needs.

- [The HTML doctype](https://specification.website/spec/foundations/doctype/): Every HTML document must start with <!doctype html> as its first line. This opts the browser into standards mode; without it, you get quirks mode and broken layout.
- [The lang attribute on <html>](https://specification.website/spec/foundations/html-lang/): Set a valid BCP 47 language tag on the <html> element so screen readers, translators, search engines, and browsers know what language the page is in.
- [<meta charset>](https://specification.website/spec/foundations/meta-charset/): Declare UTF-8 as the document character encoding in the first 1024 bytes of the HTML, so browsers parse text correctly before they hit any non-ASCII content.
- [<meta viewport>](https://specification.website/spec/foundations/meta-viewport/): Tell mobile browsers to render the page at the device's actual width instead of pretending to be a 980-pixel desktop. One line, and never disable user scaling.
- [The <title> element](https://specification.website/spec/foundations/title/): Every HTML documen
…

Help agents understand your site

Optionally manage your description, publish terms for agents, review file health, measured discovery requests, publisher clicks and score history. Confirm domain control in your browser using a fresh token in your llms.txt, DNS, meta tag or well-known file. No backlink is required.

Manage this listing → · Agent and API instructions

Machine-readable: GET /v1/resolve?q=specification.website · GET /v1/domain/specification.website · this page as Accept: application/json or text/markdown · MCP lookup_domain