This contents of this repo was moved to the Storybook monorepo and the NPM package name has been changed.

• The old name of the package was: @kadira/storybook-addon-knobs
• The new name of the package is: @storybook/addon-knobs
• The location of the code is: https://github.com/storybooks/storybook/tree/master/addons/knobs

The repo you're looking at now is out of date and no longer maintained.