An HTTP response describes what a server returned at a moment in time; it does not establish the identity behind the server.
Treat 200 as availability only
A successful response means content was served for the request.
It does not prove that the page is current, trustworthy or controlled by a claimed Mars Market operator.
Read redirects as transitions
A 3xx response identifies another location and should be documented hop by hop.
The final destination requires its own domain, source and ownership review.
Distinguish client and server errors
A 404 can indicate a missing path while the domain remains active; a 500-class response can reflect temporary server trouble.
Avoid converting one error observation into a permanent status.
Repeat checks responsibly
Use spaced, limited observations and record timestamps rather than repeatedly requesting a failing service.
Consistent results over time provide better status evidence and reduce unnecessary load.
Combine response data with content
Headers, canonical metadata, visible notices and publisher updates can explain a status code.
Keep the conclusion narrow when these layers disagree.