{ "version": "0.2.0", "rubricVersion": "0.9", "target": "https://developer.mozilla.org", "host": "developer.mozilla.org", "https": true, "measured": { "origin": "https://developer.mozilla.org", "host": "developer.mozilla.org", "https": true, "url": "https://developer.mozilla.org/en-US/" }, "redirect": { "from": "https://developer.mozilla.org/", "to": "https://developer.mozilla.org/en-US/", "status": 302, "hops": 1, "chain": [ { "url": "https://developer.mozilla.org/", "status": 302 } ], "sameSite": true }, "scannedAt": "2026-10-20T17:06:18.061Z", "durationMs": 3030, "requests": 29, "score": 61.8, "parts": { "standards": { "score": 88.3, "share": 0.7, "points": { "earned": 56.5, "available": 64 }, "counts": { "pass": 12, "warn": 2, "fail": 0, "na": 14, "total": 28 } }, "conventions": { "score": 0, "share": 0.3, "points": { "earned": 0, "available": 5 }, "counts": { "pass": 0, "warn": 0, "fail": 5, "na": 3, "total": 8 } } }, "previous": null, "level": 3, "levelName": "Machine-readable", "levelBlurb": "Text, title, headings and structured data are in the HTML, with no JavaScript run.", "levelCeiling": 3, "verdict": "Machine-readable", "confidence": 100, "confidenceLabel": "high", "fingerprint": "1f91c6124a6d8ed47c606a19ee06f9b048a90700b079980ad4350e44b5ceea30", "modules": { "commerce": { "inScope": false, "signals": [] }, "agentApi": { "inScope": false, "kinds": [], "signals": [] } }, "isCommerce": false, "commerceSignals": [], "blocked": null, "blockedNote": null, "deadline": { "ms": 60000, "reached": false }, "profile": { "id": "api", "identified": true, "declared": false, "ambiguous": [], "evidence": [ "API / developer platform (score 4), matched: A documentation path responds; API reference copy." ], "scores": [ { "id": "api", "score": 4, "signals": [ "A documentation path responds", "API reference copy" ] }, { "id": "saas", "score": 2, "signals": [ "A documentation path responds" ] }, { "id": "institution", "score": 1, "signals": [ "An organisation domain" ] } ] }, "categories": [ { "id": "discoverability", "label": "Discoverability", "score": 100, "counted": true, "pass": 6, "warn": 0, "fail": 0, "na": 0, "total": 6, "unscored": { "present": 0, "defective": 0, "absent": 0 } }, { "id": "content", "label": "Content", "score": 77.3, "counted": true, "pass": 5, "warn": 2, "fail": 0, "na": 3, "total": 10, "unscored": { "present": 0, "defective": 1, "absent": 0 } }, { "id": "botaccess", "label": "Crawler access", "score": 100, "counted": true, "pass": 1, "warn": 0, "fail": 0, "na": 0, "total": 1, "unscored": { "present": 0, "defective": 0, "absent": 2 } }, { "id": "protocol", "label": "API and agent", "score": null, "counted": false, "pass": 0, "warn": 0, "fail": 0, "na": 6, "total": 6, "unscored": { "present": 0, "defective": 0, "absent": 0 } }, { "id": "commerce", "label": "Commerce", "score": null, "counted": false, "pass": 0, "warn": 0, "fail": 0, "na": 5, "total": 5, "unscored": { "present": 0, "defective": 0, "absent": 0 } } ], "checks": [ { "id": "reachable", "category": "discoverability", "module": "core", "tier": "essential", "weight": 3, "conditional": false, "label": "Readable homepage", "why": "The homepage is the first URL every agent requests. An error or an empty page gives it nothing to read.", "skill": "agent-access", "standards": [], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "Measured at https://developer.mozilla.org/en-US/, where https://developer.mozilla.org/ redirects (HTTP 302). HTTP 200 text/html, 119 KB, 899 words of visible text. A temporary redirect is a weaker canonical signal than 301 or 308.", "evidence": "HTTP 200 · text/html · 119 KB · final https://developer.mozilla.org/en-US/", "fix": null, "part": "standards" }, { "id": "robots-txt", "category": "botaccess", "module": "core", "tier": "essential", "weight": 2, "conditional": false, "label": "robots.txt crawl policy", "why": "Crawlers read robots.txt before they fetch a page (RFC 9309). Its Sitemap line tells them where the URL list is.", "skill": "robots-txt", "standards": [ "RFC 9309" ], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "/robots.txt has 1 group and 3 rules across all groups, and 1 Sitemap line.", "evidence": "HTTP 200 · text/plain · 119 bytes · User-agent: * Sitemap: https://developer.mozilla.org/sitemap.xml Disallow: /api/ Disallow: /*/files/ Disallow: /media", "fix": null, "part": "standards" }, { "id": "sitemap-xml", "category": "discoverability", "module": "core", "tier": "essential", "weight": 2, "conditional": false, "label": "XML sitemap", "why": "A sitemap lists the URLs a site wants crawled. Google says a small, well-linked site may not need one.", "skill": "sitemap", "standards": [], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "Sitemap index https://developer.mozilla.org/sitemap.xml parses and lists 10 child sitemaps. This scan does not read the child sitemaps.", "evidence": "HTTP 200 · application/xml · 1.3 KB · root ", "fix": null, "part": "standards" }, { "id": "llms-txt", "category": "discoverability", "module": "core", "tier": "recommended", "weight": 1, "conditional": false, "label": "/llms.txt published and well-structured", "why": "A 2024 proposal for a markdown index of a site. Google Search does not use it.", "skill": "llms-txt", "standards": [ "llmstxt.org" ], "status": "fail", "points": 0, "counted": true, "excluded": null, "detail": "Not served: /llms.txt answered HTTP 404.", "evidence": "HTTP 404 · text/html · first 16 KB read", "fix": "# MDN Web Docs\n\n> The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps.\n\n## Pages\n\n- [MDN Web Docs](https://developer.mozilla.org/)\n- [](https://developer.mozilla.org/docs)\n", "part": "conventions" }, { "id": "link-headers", "category": "discoverability", "module": "core", "tier": "recommended", "weight": 1, "conditional": false, "label": "Discovery via Link response headers", "why": "A Link header (RFC 8288) points a client at a resource before it parses the HTML.", "skill": "link-headers", "standards": [ "RFC 8288" ], "status": "na", "points": 0, "counted": false, "excluded": "out-of-scope", "detail": "Not scored: there is nothing for a Link header to name. No llms.txt or markdown variant is in use, and the site serves no OpenAPI document or API catalog.", "evidence": null, "fix": null, "part": "conventions" }, { "id": "canonical", "category": "discoverability", "module": "core", "tier": "recommended", "weight": 2, "conditional": false, "label": "Canonical URL", "why": "A canonical link names the one URL a page is known by. Google treats it and redirects as canonical signals.", "skill": "canonical", "standards": [ "RFC 6596" ], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "Measured at https://developer.mozilla.org/en-US/, where https://developer.mozilla.org/ redirects (HTTP 302). Canonical https://developer.mozilla.org/en-US/ matches the page reached.", "evidence": "", "fix": null, "part": "standards" }, { "id": "http-caching", "category": "discoverability", "module": "core", "tier": "recommended", "weight": 1, "conditional": false, "label": "HTTP caching of the homepage", "why": "Cache-Control says how long the homepage may be reused. A validator lets a crawler ask whether it changed, and a 304 answer skips the body.", "skill": "http-caching", "standards": [ "RFC 9111", "RFC 9110" ], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "The homepage sends Cache-Control \"public, max-age=3600\" and ETag and Last-Modified, and a request with If-None-Match and If-Modified-Since was answered HTTP 304 Not Modified.", "evidence": "Cache-Control: public, max-age=3600 · ETag: W/\"b76b498cae7043ee81e25fd04fe755e6\" · Last-Modified: Tue, 20 Oct 2026 01:09:12 GMT · conditional GET with If-None-Match and If-Modified-Since: HTTP 304", "fix": null, "part": "standards" }, { "id": "indexing-directives", "category": "discoverability", "module": "core", "tier": "essential", "weight": 2, "conditional": false, "label": "Homepage indexable: no noindex directive", "why": "A noindex in a meta tag or in a response header keeps the page out of search results. Bing keeps it out of Copilot too.", "skill": "indexing-directives", "standards": [], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "No noindex: the homepage has no robots meta tag for robots, bingbot or googlebot, and no X-Robots-Tag header.", "evidence": "no robots meta tag for robots, bingbot or googlebot, no X-Robots-Tag header", "fix": null, "part": "standards" }, { "id": "not-found-status", "category": "discoverability", "module": "core", "tier": "recommended", "weight": 1, "conditional": false, "label": "A real 404 for a missing page", "why": "A URL that does not exist answers 404 or 410 (RFC 9110). A 200 there makes every mistyped link look like a page.", "skill": "not-found-status", "standards": [ "RFC 9110" ], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "/aws-probe-40adf5a0570b, a path that does not exist, answered HTTP 404.", "evidence": "HTTP 404 · text/html · first 16 KB read", "fix": null, "part": "standards" }, { "id": "structured-errors", "category": "discoverability", "module": "core", "tier": "recommended", "weight": 1, "conditional": false, "label": "Structured errors for JSON requests", "why": "An agent that asks for JSON and gets an HTML error page has to read a page meant for people. RFC 9457 defines a JSON error format.", "skill": "problem-details", "standards": [ "RFC 9457" ], "status": "fail", "points": 0, "counted": true, "excluded": null, "detail": "Not used: /aws-probe-40adf5a0570b, asked for JSON, answered HTTP 404 with an HTML page, not a JSON error.", "evidence": "HTTP 404 · text/html · first 16 KB read", "fix": "{\n \"type\": \"about:blank\",\n \"title\": \"Not Found\",\n \"status\": 404,\n \"detail\": \"Nothing is published at this address.\"\n}\n", "fixNote": "Send this with Content-Type: application/problem+json and the status 404 when a request for a missing path asks for JSON. Browsers can keep the HTML page (RFC 9457).", "part": "conventions" }, { "id": "llms-full", "category": "discoverability", "module": "core", "tier": "recommended", "weight": 1, "conditional": false, "label": "/llms-full.txt expanded context", "why": "A convention that puts a site's text in one file. The llms.txt proposal does not define it.", "skill": "llms-full-txt", "standards": [], "status": "na", "points": 0, "counted": false, "excluded": "out-of-scope", "detail": "Not scored: /llms.txt is not served (HTTP 404), so /llms-full.txt is not asked for.", "evidence": null, "fix": null, "part": "conventions" }, { "id": "markdown-negotiation", "category": "content", "module": "core", "tier": "recommended", "weight": 1, "conditional": false, "label": "Markdown content negotiation", "why": "Some coding agents ask for text/markdown. Google Search does not use markdown.", "skill": "markdown-negotiation", "standards": [ "RFC 9110" ], "status": "fail", "points": 0, "counted": true, "excluded": null, "detail": "The homepage answered `Accept: text/markdown, text/html;q=0.5` with HTML, which is a valid response.", "evidence": "HTTP 200 · text/html · Vary: Accept-Encoding · markdown body: no", "fix": "Answer a request whose Accept header prefers text/markdown with a markdown version of the same page, at the same URL.\n- On a CDN that converts HTML to markdown, turn that conversion on for the site.\n- On a CMS or a static build, publish one .md file per page, and serve it when Accept prefers text/markdown.\nSend Content-Type: text/markdown; charset=utf-8 with the markdown.\nSend Vary: Accept with both the markdown and the HTML, so a shared cache keeps them apart.", "part": "conventions" }, { "id": "headings", "category": "content", "module": "core", "tier": "essential", "weight": 2, "conditional": false, "label": "Semantic heading structure", "why": "Headings outline the page for screen readers and for any client that splits text by section.", "skill": "semantic-headings", "standards": [ "WCAG 2.2" ], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "1 H1, 4 H2s, and 8 H3s in an outline of 13 headings, with no skipped level.", "evidence": "outline: H1 H2 H3 H3 H3 H3 H2 H3 H3 H3 H3 H2 H2", "fix": null, "part": "standards" }, { "id": "meta", "category": "content", "module": "core", "tier": "essential", "weight": 2, "conditional": false, "label": "Title and description", "why": "The title and the description say what a page is about. Google uses them for the title link and the snippet.", "skill": "page-metadata", "standards": [], "status": "warn", "points": 0.5, "counted": true, "excluded": null, "detail": "Title \"MDN Web Docs\" (12 characters) and a description of 145 characters. The first H1 \"Resources for Developers, by Developers\" shares 0 of 2 words with the title, brand names aside. Microsoft's guide to AI search answers (October 2025) asks for an H1 that matches the title or closely reflects it.", "evidence": "title (12 characters): MDN Web Docs · description (145 characters): The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps. · first H1: Resources for Developers, by Developers", "fix": null, "fixNote": "Give the first H1 and the title the same subject. Either can change, and brand names do not count.", "part": "standards" }, { "id": "jsonld", "category": "content", "module": "core", "tier": "essential", "weight": 3, "conditional": false, "label": "JSON-LD structured data", "why": "Structured data names the entity a page describes. Google reads JSON-LD, Microdata and RDFa alike.", "skill": "structured-data", "standards": [ "schema.org" ], "status": "warn", "points": 0.5, "counted": true, "excluded": null, "detail": "1 RDFa item on the homepage, and no top-level node names the page entity: BreadcrumbList is a structural type.", "evidence": "JSON-LD: 0 blocks, 0 parsed · schema.org @context: no · Microdata: 0 items · RDFa: 1 items · top-level types: BreadcrumbList", "fix": "", "part": "standards" }, { "id": "lang", "category": "content", "module": "core", "tier": "recommended", "weight": 1, "conditional": false, "label": "Language declaration and multilingual access", "why": "The lang attribute names the language of the text. WCAG 3.1.1 requires it at level A. Google reads hreflang, not lang.", "skill": "language-declaration", "standards": [ "WCAG 2.2", "BCP 47" ], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "html lang=\"en-US\" is a well-formed BCP 47 tag, with no hreflang alternates.", "evidence": "html lang=\"en-US\" · alternates: none · content-language: (none)", "fix": null, "part": "standards" }, { "id": "no-js-fallback", "category": "content", "module": "core", "tier": "essential", "weight": 3, "conditional": false, "label": "Content that needs no JavaScript", "why": "Several AI crawlers do not run JavaScript. Text that appears only after scripts run is invisible to them.", "skill": "server-rendering", "standards": [], "status": "pass", "points": 1, "counted": true, "excluded": null, "detail": "6265 characters of text are in the HTML before any script runs.", "evidence": "static text: 6265 characters · inside