low

410 Gone

The resource existed but has been permanently removed. Unlike 404, this explicitly tells clients the resource won't come back.

Common Causes

// Signal to search engines to de-index
if (isDeleted) {
  return new Response('Resource permanently removed', { status: 410 });
}

410 tells search engines to de-index the page, while 404 may not.

ObserveOne tracks resource lifecycle and validates 410 responses are intentional.

The server cannot find the requested resource. The URL may be wrong, the resource may have been deleted, or the route doesn't exist.

The server cannot process the request due to malformed syntax, invalid parameters, or bad encoding.

The request requires authentication. The client must provide valid credentials.

The server understood the request but refuses to authorize it. Authentication won't help — the user lacks permissions.

The HTTP method (GET, POST, PUT, DELETE) is not supported for this endpoint.