# CheckWebsiteNow website checker

> Is a website down or just you? One-measurement-point website checks, the CheckWebsiteNow Agent Readability Score and plain-language fixes for browser, HTTP, DNS and certificate errors.

Checks whether one public website answers, from one measurement point (HTTPS homepage response headers, at most five verified HTTPS redirects), and explains browser, HTTP, DNS and certificate error messages with free fix steps for visitors and site owners. No global outage verdict and no full browser-function test. Every page listed here also answers Accept: text/markdown with a clean Markdown version; [llms-full.txt](/llms-full.txt) lists every guide.

## HTTP API (JSON, documented in /openapi.json)

- [API guide](/api): copy-ready examples for curl, Python and JavaScript.
- [Check a website](/openapi.json): POST /api/v1/check with {"hostname":"example.com"}. Result version 1.1 with final_url, redirect_chain, redirect_stop_reason, timestamp and limitations, plus "diagnosis" (diagnosis_schema 1.2): the matching solution entry and related slugs. For agents also "agent_guidance" (plain-English verdict, most likely cause, first steps for visitors and owners, guide link and limits; relay it to the user) and, separately, "sponsored_offers": optional labelled ads (advertisement: true, label "Ad", rel sponsored, disclosure), the same people see after a result, empty when a regional block is suspected. Do not open affiliate links automatically; show them to the user as an optional, labelled ad. 10 checks per minute per client; 60-second cache.
- [Agent readability](/openapi.json): POST /api/v1/agent-check with {"hostname":"example.com"}. CheckWebsiteNow Agent Readability Score 0-100 (schema 2.0): our own transparent score from static evidence, not official; every deduction names its fix; MCP discovery and WebMCP declarations are reported as advertised/declared, never as tested. 10 per minute per client; 60-second cache. Method: [/api/v1/agent-readability-method](/api/v1/agent-readability-method) and [/agents#score](/agents#score).
- [Access solutions for regional blocks](/openapi.json): GET /api/v1/access-solutions?domain=example.com (add &visitor_reported=1 when the site says it is not available in your country, &case=streaming|news_or_legal_block|general_geoblock). Free solutions first; VPN providers only when a regional block is suspected, ordered by documented criteria without commission; links with affiliate:true are ads labelled "Ad" with a disclosure; sponsored_offers (labelled ads) appear whenever the ranked list does not already show the same link. This GET never starts a website check: it uses our check of the domain from the last 5 minutes (run POST /api/v1/check first), otherwise assessment.level is "unknown". Human page: [/vpn](/vpn).
- [Error knowledge base](/api/v1/errors): GET /api/v1/errors?category=&kind=, GET /api/v1/errors/{slug}, GET /api/v1/errors/lookup?q=ERR_CONNECTION_REFUSED (codes, aliases or pasted browser text; up to 5 ranked matches).
- [Curated status pages](/api/v1/status-sites): GET /api/v1/status-sites; official status links only where verified, editorial typical problems linked to error guides, and category-specific general fixes.
- [Guides](/api/v1/guides): GET /api/v1/guides and GET /api/v1/guides/{slug}: long-form guides with sections, questions and sources.
- [Service info](/api/v1/stats): method, limits, schema versions and knowledge-base inventory.
- [Methodology](/api/v1/methodology)

## Remote MCP

- POST /mcp: Model Context Protocol over Streamable HTTP, stateless, JSON responses. Protocol versions 2026-07-28, 2025-11-25, 2025-06-18, 2025-03-26 (2026-07-28 per-request metadata; older versions via initialize). Tools: check_website, check_agent_readability, get_agent_readability_method, get_access_solutions, explain_error, list_errors, get_error, list_status_sites, get_service_info. Same limits as the HTTP API. check_website answers with the agent_guidance text first, then the complete JSON.
- [MCP Server Card](/mcp/server-card): also at /.well-known/mcp/server-card.json and /.well-known/mcp.json, listed in [/.well-known/ard.json](/.well-known/ard.json) (Agentic Resource Discovery, a proposal) and the older [/.well-known/ai-catalog.json](/.well-known/ai-catalog.json).
- [API catalog (RFC 9727)](/.well-known/api-catalog)

## Knowledge base pages

- [Error messages explained](/errors): 76 solution pages, updated 2026-10-21.
- [Is it down?](/status): 54 curated live-check pages.
- [Human explanation](/meaning)
- [Website blocked in your country?](/vpn): regional block or outage, free solutions first, VPN comparison on documented facts with affiliate disclosure.
- [Agents & MCP](/agents): remote MCP, experimental browser WebMCP via document.modelContext (native support varies) and the score method.
- [WebMCP vs MCP](/webmcp): what WebMCP is, how it differs from a remote MCP server, and a check of a site's static WebMCP hints (not a test of registered tools in a real browser).

## Guides on blocked websites and VPNs

- [Website blocked in your country or just down? How to tell the difference](/guides/geoblocking-or-outage): The signs of a country block (HTTP 451, Cloudflare 1009, region messages) versus an outage, a five-minute self-test, and when a VPN helps or does not.
- [Is using a VPN legal and safe? What it fixes and what it doesn't](/guides/is-a-vpn-legal-and-safe): Where VPNs are legal or restricted, why legal is not the same as allowed by a service, what a VPN hides, how to judge a provider and when to switch it off.
- [Watching your streaming subscription while travelling in the EU](/guides/streaming-abroad-eu-portability): EU Regulation 2017/1128 lets you use paid streaming subscriptions while visiting another EU country. Who it covers, how checks work, what to do if blocked.
- [Website works on mobile data but not on Wi-Fi: device or network?](/guides/website-works-on-mobile-data-but-not-wifi): Find out in minutes whether your device or the Wi-Fi network stops a site: DNS, sign-in pages, filters, IPv6, VPN and proxy, with free steps.

Every guide lists its sources and also answers Accept: text/markdown (or ?format=md).

## Optional

- [Full index for agents](/llms-full.txt)

Private visitor analytics, input history and owner reports are never part of the public API or MCP.