Because I have 3 tests covering 67% of the code base and my only docs are blog posts. If you're way more adventurous than I am, the code is available at https://github.com/chainreactionmfg/cara for your daring consumption.
Edit: I didn't mean it won't be available for others later, just not quite yet. I'd like to use it internally first, then once I've got any wrinkles ironed out, I'll polish cara up and make it available. There's quite a bit of polish required however, such as travis/tox integration, a proper readme and docs, and more/better tests.