I've created CouchBase plugin for Nagios. I used Python for plugin. I put plugin in Github. You can access here. Nagios Plugin Couchbase is available under the GPLv3. Your suggestions and feedbacks will be valued and highly appreciated.
Nagios plugin couchbase supply to monitor a lot of summary statistics:
Cache miss ratio, creates per second, disk read, high and low watermark, set per second, memory usage, operations per second.. etc.
You can monitor vbucket resources with option "--vbucket". You can see all option using "--help" parameter and you should read from Readme for more information about usage. And a screenshot: