CLEAR CHECKS. THE SAME EVIDENCE.

Made to be understood.
By people and agents.

The form and HTTP API use the same checker. Every result includes its measurement scope and uncertainty.

HTTP API

Send one public domain to POST /api/v1/check with Content-Type: application/json. Paths, credentials, IP addresses and custom ports are rejected.

{"hostname":"example.com"}

OpenAPI description · Machine-readable methodology · Agent discovery guide. Checks are limited to ten per minute per client; recent results may be reused for sixty seconds. Busy-service or rate-limit errors are not target-outage verdicts.

What we measure

Every requested destination is resolved and all returned addresses must be public. We connect to the verified numeric address while checking the HTTPS certificate for the hostname. Up to five safe HTTPS redirects are followed within one ten-second measurement budget. HEAD requests can fall back to GET response headers for 404, 405 or 501 responses. The quick response check does not inspect page contents. The separate content check below reads bounded public documents only when requested.

final_url, redirect_count, redirect_chain and per-request evidence describe the actual observations. A redirect to an error remains an error. Sensitive query strings are omitted from exposed URLs.

WebMCP

In supporting experimental browsers, document.modelContext registers check_public_website, check_agent_readability and get_check_methodology. A website check updates the same visible result. Ordinary browser use and the HTTP API work without WebMCP. Chrome’s original documentation.

WebMCP is experimental. This is not a remote MCP server. There is no promise of support in every browser, an agent-directory listing or improved search ranking.

Helping agents use your own website

A public response, readable content and callable browser actions are separate questions. Our quick check answers the first; it does not inspect another site's content or calculate a WebMCP score.

Six practical steps for website owners → Learn about clear text and controls, search versus training bots, hosting protection, optional llms.txt and experimental WebMCP. These steps are not a promise of search inclusion or improved ranking.

Public evidence, private analytics

Utility observations are public. Visitor records, the project cockpit and improvement proposals are not available on this public service. There are no publicly readable session recordings.

Limits

• One measurement point, not global coverage.
• A successful response does not test sign-in, checkout or every page.
• Only one verified resolved address is contacted per request. Other addresses may behave differently.
• Combined check time is not page-loading speed.
• No long-term uptime percentage or verified visitor count is claimed.