This package uses the undocumented Google toolbar spellcheck api, results are returned in xml, parsed and enhanced

There is only one export... the check function
it takes 2 parameters
1) the text to check
2) a callback to return the result to (first argument is err and second is res)

Usage:
var spell = require('gspell');

spell.check('ths is a tst ub the spell chek spetem',function(err,res){
console.log(res);
});

a javascript object is returned as the second argument to the callback

the res.c array has the spelling suggestions as well as where the mispelling was found in the text and
a confidence score of how sure it is about the suggestion