Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add humanerd-drew/opencode-drewgent --skill specification-websitegit clone --depth 1 https://github.com/humanerd-drew/opencode-drewgentWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/humanerd-drew/opencode-drewgent/specification-website)<a href="https://agentmods.dev/skills/humanerd-drew/opencode-drewgent/specification-website"><img src="https://agentmods.dev/badge/skills/humanerd-drew/opencode-drewgent/specification-website.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00000 | $0.01551 |
| Opus 5 | $0.00000 | $0.00776 |
| Sonnet 5 | $0.00000 | $0.00310 |
| Haiku 4.5 | $0.00000 | $0.00155 |
Grade A, and why
specification-website scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 118 lines — stays where its author put it; the contents beside it link to each section on GitHub.
name: specification-website title: specification.website — The Website Specification description: Query and apply The Website Specification — a platform-agnostic specification of what a good website does, with each item tagged required, recommended, optional, or avoid. Use when the user asks what their site should have, whether something is required, how to audit a URL, what's missing for agent readiness, or anything else where you'd otherwise be guessing at web best practice. Backs answers with primary sources (WHATWG, W3C, IETF RFCs, IANA, WCAG). Available as Markdown over HTTP and as an MCP server with search, list, fetch, checklist, and audit tools. type: skill space: growth tags: [skill, spec, web-standards, agent-readiness, audit] source: https://specification.website/ author: Joost de Valk license: CC BY 4.0 (content) / MIT (code) created: 2026-06-01 updated: 2026-06-01 links:
- "[[@action/skills/SKILL-INDEX]]"
- "[[skills/YOUR_SITE]]"
- "[[skills/seo-audit]]"
- "[[@memory/knowledge/obsidian-vault-site-principle]]"
- "[[@identity/brain/rules]]"---
specification-website
The Website Specification is a single source of truth for what a good website does. Ten categories, ~100 pages, every item tagged with a status. It ships in three machine-readable forms: per-page Markdown, llms.txt / llms-full.txt, and an MCP server.
When to use this skill
- The user asks "what should my site have", "is X required", "audit this URL", "what does the spec say about Y", or anything similar.
- You're reviewing a site and want to cite primary standards rather than vendor blog posts.
- You need a machine-readable contract for a platform-agnostic audit.
Quickest path — MCP
If you can speak MCP, use it. The server is stateless Streamable HTTP, no auth, wide-open CORS.
- Endpoint:
https://mcp.specification.website/mcp - Server card:
https://specification.website/.well-known/mcp/server-card.json - Protocol revision: 2025-03-26
Tools:
| Tool | Purpose |
|---|---|
search(query, limit?) |
Full-text search across every page. |
list_topics({ category?, status?, limit? }) |
Filtered index — slug, title, status, summary, URL. |
get_topic({ slug }) |
Full canonical Markdown for one page, including its cited sources. |
get_checklist({ category?, status? }) |
Tickable Markdown checklist. |
get_categories() |
The ten categories with counts and summaries. |
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 118 lines · 0 tokens per session scan A d2bb2a8dbae0
specification-website is a skill published in the GitHub repository humanerd-drew/opencode-drewgent (2 stars, last pushed 1mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,551 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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