Available in npm for convenience. Unofficial. Source: http://bohemiancoding.com/sketch/tool/
This package version follows the original version of SketchTool. I'll update the binary when new one is released. Please file an issue, if I don't.
var sketchtool = require('sketchtool')
sketchtool('dump /path/to/file.sketch', function (error, stdout, stderr) {
// callback
})
var sketchtool = require('sketchtool')
console.log('This is path to sketchtool binary:', sketchtool.binaryPath)