F
Why this grade
This is a failing grade. The foundational signals agents look for OpenAPI specification discovery and Public MCP registry listing aren't in place yet — start there before anything else.
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Quick wins
Low-cost fixes that would nudge this grade up.
- JSON error bodies for API callers Return a JSON error body (application/json or application/problem+json), not an HTML page, when the caller sends `Accept: application/json`.
- /ai.txt AI-crawler directives Add a short `/ai.txt` at the site root declaring your AI-crawler usage terms (see spawning.ai/ai-txt).
- /llms-full.txt long-form index Add a `/llms-full.txt` — the full-text companion to llms.txt with your key docs inlined for LLMs (see llmstxt.org).
- /.well-known/agent.json (A2A AgentCard) Publish an A2A AgentCard at `/.well-known/agent.json` with name, description, skills, and endpoints.
- /.well-known/ai-plugin.json manifest Publish a `/.well-known/ai-plugin.json` manifest with name_for_model, description_for_model, and an api block.
Blocking issues
High-weight checks that aren't passing.
- OpenAPI specification discovery No OpenAPI spec found at any of 9 conventional paths.
- Public MCP registry listing Host www.anthropic.com not listed in any of 2 registry/registries consulted.
Per-category breakdown
| Category | Score | Percent |
|---|---|---|
| Anti Bot | 15 / 15 | |
| Api | 0 / 15 | |
| Crawl | 23 / 23 | |
| Docs | 3 / 14 | |
| Html Meta | 0 / 8 | |
| Identity | 10 / 10 | |
| Onboarding | 0 / 6 | |
| Protocols | 0 / 10 |
Findings (33)
Anti Bot · 2
| Check | Status | Points | Notes |
|---|---|---|---|
| Anti-bot interstitial | pass | 10 / 10 | No anti-bot interstitial markers on a single polite homepage request — behavioural anti-bot can still challenge real crawler traffic. |
| User-agent sniffing | pass | 5 / 5 | Homepage responses for default and curl UAs are effectively identical. |
Api · 3
| Check | Status | Points | Notes |
|---|---|---|---|
| GraphQL introspection | skip | — | No GraphQL endpoint found at any of 3 conventional paths. |
| JSON error bodies for API callers | fail | 0 / 5 | HTTP 404 served an HTML body for an API-like caller (Accept: application/json). |
| OpenAPI specification discovery | fail | 0 / 10 | No OpenAPI spec found at any of 9 conventional paths. |
Crawl · 3
| Check | Status | Points | Notes |
|---|---|---|---|
| RSS/Atom feed | skip | — | No RSS/Atom feed found at probed paths or via `<link rel="alternate">`. |
| robots.txt AI-agent rules | pass | 13 / 13 | All 13 documented AI user-agents can crawl /. |
| XML sitemap discovery | pass | 10 / 10 | Sitemap at /sitemap.xml (urlset, 515 entries). |
Docs · 2
| Check | Status | Points | Notes |
|---|---|---|---|
| Docs platform discoverability | warn | 3 / 6 | Docs found at /docs but platform is custom — crawler-friendliness is unknown. |
| SDK availability across languages | fail | 0 / 8 | No SDKs discoverable via npm, PyPI, or the docs page. |
Html Meta · 3
| Check | Status | Points | Notes |
|---|---|---|---|
| JSON-LD structured data | fail | 0 / 8 | No JSON-LD blocks on the homepage. |
| meta description | info | — | Meta description present (121 characters) (informational — not graded). |
| Open Graph tags | info | — | All three core Open Graph tags present on the homepage (informational — not graded). |
Identity · 3
| Check | Status | Points | Notes |
|---|---|---|---|
| Email auth (SPF, DMARC, DKIM) | info | — | No SPF / DMARC / DKIM found — domain has no email auth (informational — email trust, not agent discoverability). |
| security.txt responsible-disclosure declaration | info | — | security.txt at https://www.anthropic.com/.well-known/security.txt declares a Contact (informational — a human security-researcher signal, not graded). |
| TLS + HSTS + HTTPS redirect | pass | 10 / 10 | Valid TLS cert (issuer: C=US, O=Let's Encrypt, CN=YE1, expires 2026-10-06), http → https redirect confirmed. (HSTS max-age=3600 (below the 6-month preload threshold) — informational.) |
Llm Training · 3
| Check | Status | Points | Notes |
|---|---|---|---|
| Common Crawl index presence | info | — | 50 pages from www.anthropic.com in CC-MAIN-2026-30 (informational — corpus presence, not graded). |
| Hacker News mentions | info | — | 50 verified HN mention(s) of www.anthropic.com (informational — popularity signal, not graded). |
| Wikipedia article | info | — | Wikipedia article "Anthropic" links to www.anthropic.com (https://www.anthropic.com/) (informational — corpus knowledge, not graded). |
Onboarding · 1
| Check | Status | Points | Notes |
|---|---|---|---|
| API-key / signup path discoverability | fail | 0 / 6 | No signup, API-key, or developer page discoverable by anchor text or conventional path. |
Protocols · 2
| Check | Status | Points | Notes |
|---|---|---|---|
| Public MCP registry listing | fail | 0 / 10 | Host www.anthropic.com not listed in any of 2 registry/registries consulted. |
| A2A AgentCard conformance | skip | — | No AgentCard at /.well-known/agent.json — nothing to grade. |
Registries · 3
| Check | Status | Points | Notes |
|---|---|---|---|
| GitHub public repository | skip | — | No GitHub repositories attributable to www.anthropic.com — name matches without a verifiable attribution signal are not counted. |
| npm SDK package | skip | — | No npm packages attributable to www.anthropic.com — name matches without a verifiable attribution signal are not counted. |
| PyPI SDK package | skip | — | No PyPI package at the 2 name(s) probed for www.anthropic.com. |
Root Level · 3
| Check | Status | Points | Notes |
|---|---|---|---|
| /ai.txt AI-crawler directives | skip | — | No /ai.txt present (404) — this is a secondary signal, not a negative one. |
| /llms-full.txt long-form index | skip | — | No /llms-full.txt present (404). |
| /llms.txt index for LLMs | error | — | Transport error fetching https://www.anthropic.com/llms.txt: Idle timeout reached for "https://www.anthropic.com/llms.txt". |
Well Known · 5
| Check | Status | Points | Notes |
|---|---|---|---|
| /.well-known/agent.json (A2A AgentCard) | skip | — | No /.well-known/agent.json present (404). |
| /.well-known/ai-plugin.json manifest | skip | — | No /.well-known/ai-plugin.json present (404). |
| /.well-known/mcp.json (Model Context Protocol) | skip | — | No /.well-known/mcp.json present (404). |
| OpenID Connect configuration + dynamic registration | error | — | Transport error fetching https://www.anthropic.com/.well-known/openid-configuration: Idle timeout reached for "https://www.anthropic.com/.well-known/openid-configuration". |
| /.well-known/openapi.{json,yaml} | skip | — | No OpenAPI spec at either well-known path. |
Scan history
| When | Grade | Score | Checks | Change | Open scan |
|---|---|---|---|---|---|
| 21 Aug 2026, 07:40 | F | 28 | 33 | Open |
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