C
Why this grade
A middle-of-the-pack C. Credit on robots.txt AI-agent rules, but the biggest gaps are on OpenAPI specification discovery and JSON-LD structured data — closing those would lift this toward a B.
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Quick wins
Low-cost fixes that would nudge this grade up.
- /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.txt index for LLMs Add a short `/llms.txt` Markdown index of your key URLs (see https://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.
- /.well-known/mcp.json (Model Context Protocol) Publish an MCP manifest at `/.well-known/mcp.json` declaring your server, capabilities, or tools.
Blocking issues
High-weight checks that aren't passing.
- OpenAPI specification discovery No OpenAPI spec found at any of 9 conventional paths.
Per-category breakdown
| Category | Score | Percent |
|---|---|---|
| Anti Bot | 15 / 15 | |
| Api | 0 / 10 | |
| Crawl | 23 / 23 | |
| Docs | 0 / 14 | |
| Html Meta | 0 / 8 | |
| Identity | 10 / 10 | |
| Onboarding | 0 / 6 | |
| Protocols | 10 / 10 | |
| Registries | 5 / 5 |
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 | error | — | Transport error fetching https://anthropic.com/this-path-definitely-does-not-exist-agentdisco-2d5fcba0efe2: Idle timeout reached for "https://www.anthropic.com/this-path-definitely-does-not-exist-agentdisco-2d5fcba0efe2". |
| 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 | fail | 0 / 6 | No docs found at any of the conventional paths. |
| 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 | — | Email auth present: SPF + DMARC + DKIM (informational — mail trust/deliverability, not graded). |
| security.txt responsible-disclosure declaration | error | — | Every security.txt probe returned a non-404 error status — cannot assess. |
| TLS + HSTS + HTTPS redirect | pass | 10 / 10 | Valid TLS cert (issuer: C=US, O=Let's Encrypt, CN=YE2, expires 2026-09-04), 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 anthropic.com in CC-MAIN-2026-30 (informational — corpus presence, not graded). |
| Hacker News mentions | info | — | 50 verified HN mention(s) of anthropic.com (informational — popularity signal, not graded). |
| Wikipedia article | info | — | Wikipedia article "Anthropic" links to 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 | pass | 10 / 10 | Listed in 1 registry/registries: glama. |
| A2A AgentCard conformance | skip | — | No AgentCard at /.well-known/agent.json — nothing to grade. |
Registries · 3
| Check | Status | Points | Notes |
|---|---|---|---|
| GitHub public repository | pass | 5 / 5 | 8 attributable repo(s): anthropics/anthropic-sdk-python (owner profile website); anthropics/anthropic-sdk-typescript (owner profile website); anthropics/anthropic-sdk-go (owner profile website); anthropics/anthropic-cli (owner profile website); anthropics/anthropic-sdk-csharp (owner profile website). |
| npm SDK package | skip | — | No npm packages attributable to anthropic.com — name matches without a verifiable attribution signal are not counted. |
| PyPI SDK package | skip | — | PyPI package(s) exist at probed name(s) (anthropic) but none carry a verifiable attribution signal — name-existence alone is not counted. |
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 | error | — | Transport error fetching https://anthropic.com/llms-full.txt: Idle timeout reached for "https://www.anthropic.com/llms-full.txt". |
| /llms.txt index for LLMs | skip | — | No /llms.txt present (404). |
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 | skip | — | No /.well-known/openid-configuration — site does not advertise an OIDC provider. |
| /.well-known/openapi.{json,yaml} | skip | — | No OpenAPI spec at either well-known path. |
Score over time
- Latest
- 56 ▼ 3
- Best
- 59
- Worst
- 56
- Scans
- 3
Scan history
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