Creating package with multiple document binaries, uploading with superagent.

Hi! I have been trying to upload multiple documents with a post request to '/api/packages' (the sandbox) url and getting getting the error indicating the number of documents sent in the payload is different from what I attached, Could have a look at the code and let me know, what I am missing?

var httpReq = require('superagent');
var _ = require('lodash');

var createPackageReq = httpReq
                                    .post(config.esignature.host + '/packages')
                                    .set('Content-type', 'multipart/form-data')
                                    .set('Accept', 'application/json')
                                   .set(SILANIS_AUTHORIZATION); //my API Key

//req is the request passed on to this function from my UI
_.keys(req.body.documents).forEach(function(docName) {
		documents.push({name: docName});
		createPackageReq
			.attach(docName, req.body.documents[docName].result.path);
});
var stringData = JSON.stringify({documents: documents});
createPackageReq
	.field('payload', stringData)
	..end(function(err, resp) {
			if(err) {
				// console.log(resp.error);
				throw err;
			}
			if (resp.statusCode === 200) {
				// console.log(resp.body);
				res.send(resp.body);
			} else {
				res.sendStatus(resp.statusCode);
			}
		});

and below is the error I am getting,

 [Error: cannot POST /api/packages (400)]
  status: 400,
  text: '{
	"entity":null,
	"messageKey":"error.validation.package.wrongNumberOfFiles",
	"technical":"Number of uploaded files does not match number of documents specified in package.",
	"packageId":null,
	"message":"Number of uploaded files does not match number of documents specified in package.",
	"code":400,
	"name":"Validation Error"
}',
  method: 'POST',
  path: '/api/packages' 

Thanks, Vinay