If properly responding to the health check with a message body *res.status(200).send('');* as the documentation states causes the health checks to fail, that would indeed warrant an issue to be reported in the PIT (public issue tracker).
Note that responding to health checks is not required as even a 404 response from your application tells nginx that you application is alive (as it responded saying it cannot find the requested resource 404). -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to google-appengine+unsubscr...@googlegroups.com. To post to this group, send email to google-appengine@googlegroups.com. Visit this group at https://groups.google.com/group/google-appengine. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/38d01d46-8c41-42f3-94cf-37ce0d10d711%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.