Broadly, these scripts are presented for educational use, to help the reader better understand how 1Password works, and perhaps to build new tools for interacting with 1Password.
The specific code itself is hereby released for free use. If you build anything really cool with it, please acknowledge the role of this code and/or associated blog posts, talks, etc., in how you were able to build your system.
If you really want to use the code itself, go ahead. But really, it's probably best that you just use this as inspiration and write your own code. I mean, it works for what it is, but I wouldn't want to build a product around it.
If I had to specifically pick a common Open Source license for what's here, I'd have to call it "CC-BY-SA":
Creative Commons - Attribution + ShareAlike
"CC-BY-SA"
Attribution required, remixes and commercial use allowed.
But again, just use these tools as a starting point. Safe handling of password data is far too important to trust to my hacked-together code.