Another thought might be to write a simple javascript library that thinly wraps the couchdb interface to make it (even!) friendlier both for command line use in something like firebug and within scripts in general.

Such a library could be folded (npi) into futon to make your exercise above a little easier as well as put it into the hands of everyone who has couchdb. Futon could even use it to include a text field within the page giving a command line interface apart from firebug…