@alex @Boyka @josh I don't think "service unavailable" makes sense here because in fact the service _is_ available but access is being denied for whatever reason

"403 forbidden" seems clear enough to me

"450 Blocked by Windows Parental Controls" would be amusing

of course the page should just clearly state "we think you're a bot" in plain english and at that point it's all sort of irrelevant

in fact you might just return 200 and a static page that explains what's going on