This solves a problem that requestb.in does not. Namely, endpoints that predictably return various HTTP headers or HTTP content. This isn't about just testing t

This solves a problem that requestb.in does not. Namely, endpoints that predictably return various HTTP headers or HTTP content. This isn't about just testing to see what your app is sending. This is about testing how your application or HTTP client or whatever handles various weird HTTP responses and features. If I need to test how my application responds to a relative URL in a Location header, I can hit the /relative-redirect/:n endpoint. Same for Absolute urls via /absolute-redirect/:n. The If-Not-Modified stuff is also helpful.