So the issue seems to be sporadic. I'm not sure how exactly the filter gets triggered, but when it does, the rewritten page gets cached by IE so future requests are guaranteed to fail until the browser cache is emptied.
I also found this Microsoft document that describes a custom header, X-XSS-Protection, that can be used to disable the filter. Obviously, this should only be used on a dev system in hosted mode.
To disable the filter, add the following header to your server configuration:
X-XSS-Protection: 0