Rubric v1.3
Every scan is scored against the published rubric below. Rubric changes require two approvals — EAC engineering (measurement correctness) and Evangent leadership (grading integrity) — and every change bumps the version string. Historical scans retain the rubric version that was active when they ran.
The two-tier composite
v1.3 replaces the v1.2 four-categories-weighted model with a two-tier Hygiene + Frontier composite. Hygiene measures whether agents can read the site at all — sensible robots.txt, clean HTML, content reachable without JavaScript, semantic structure, decent token efficiency. Frontier measures genuinely ahead-of-the-curve agent-native features — Accept: text/markdown,/.well-known/mcp.json, WebMCP tool declarations, Content-Signal headers, A2A agent cards. Most well-built 2026 sites land in the B range on hygiene alone; Frontier is what lifts a site to A and A+.
Composite formula
// Content site
composite = hygiene * 0.85 + frontier * 0.15
// Interactive site
composite = hygiene * 0.75 + frontier * 0.25Interactive sites get more frontier credit because WebMCP tools and MCP endpoints genuinely matter more there — an e-commerce site with agent tools is materially more usable than one without.
Site-type classification
Sites are classified automatically as Content (blog, church, news, docs, nonprofit) or Interactive (SaaS, e-commerce, booking, dashboards). Classification uses schema.org types, form patterns, and URL hints, and can be overridden by the user.
Hygiene checks
Hygiene is a weighted average of three sub-categories. The sub-category weights roll up into the Hygiene composite.
| Sub-category | Weight in Hygiene |
|---|---|
| Crawler accessibility | 30% |
| Content readability | 35% |
| Semantic structure | 35% |
| Check | Sub-category | Within-sub-category weight |
|---|---|---|
| robots.txt AI-agent policy | crawler | 45% |
| JavaScript dependency | crawler | 40% |
| Login / paywall wall | crawler | 15% |
| Accept: text/markdown negotiation | readability | 15% |
| Content-to-chrome ratio | readability | 45% |
| Token efficiency | readability | 40% |
| JSON-LD / schema.org | semantic | 30% |
| Open Graph & Twitter Cards | semantic | 20% |
| Heading hierarchy | semantic | 20% |
| Language declaration | semantic | 10% |
| sitemap.xml | semantic | 20% |
Frontier checks
Frontier is generous at the low end and demanding at the high end. A site with any two of the top three (content negotiation, MCP, WebMCP or rich structured data) scores 50+. A site with all three plus decent minor signals scores 90+. The top scores (95+) are reserved for sites that have genuinely built comprehensive agentic-web support.
| Check | Weight in Frontier | Applies to |
|---|---|---|
| Accept: text/markdown negotiation | 25% | both |
| MCP server discovery | 25% | both |
| WebMCP tool declarations | 20% | interactive |
| Rich structured data | 20% | content |
| Content-Signal response header | 10% | both |
| A2A agent card | 10% | both |
| llms.txt / ai.txt intent signal | 5% | both |
| .md mirror | 5% | both |
Letter grades
| Composite | Grade | Meaning |
|---|---|---|
| 95–100 | A+ | Agentic-web leadership. Genuinely exceptional. |
| 88–94 | A | Ahead of the curve on AI readability. |
| 78–87 | B | Fundamentals solid; frontier features would push to A. |
| 65–77 | C | Readable, but real gaps. Clear next steps. |
| 50–64 | D | Serious issues; agents struggle here. |
| 0–49 | F | Unreadable to most agents. |
Human-only ceiling (§4.6)
A site that scores below 15 on Frontier — meaning essentially no agent-native features — has its composite capped at 85 (top of B) regardless of how strong its Hygiene score is. This is a softer replacement for the v1.2 D+ penalty: pristine HTML and perfect semantic structure still top out at B until the site adds some agent-native surface. The cap is disclosed on every affected scorecard — it’s aspirational, not punishing: B is a respectable grade that says “you’re doing the basics right” and the cap preserves a meaningful difference between sites that have invested in the agentic web and sites that have only invested in the traditional web.
Where we're opinionated
The rubric tracks live agentic-web protocols — Accept: text/markdown, /.well-known/mcp.json, WebMCP, Content-Signal — because empirical data shows these are what agents actually use in 2026. llms.txt and ai.txt are kept as minor signals of intent, not load-bearing checks; independent log studies show ~0.1% of AI crawler requests fetch them.
Governance
Rubric changes are tracked in the lib/rubric/ directory of the open-source repo, one file per version. Breaking changes live alongside the previous version so historical scans continue to read their own version's scoring logic. The rubric is reviewed quarterly against the current agentic-web landscape.