[dragonwriter]

The thing about the pipe isn't, as I see it, a protocol issue, but a UI issue: that is, a simple method of telling your shell (browser, for an OS) to compose tools rather than requiring you to interact with each of them interactively.

To be fair, I don't think we have a good way to do that with graphical OS shells even on Unix, just CLIs, so its probably not surprising that we don't have it in web browsers.