Set the window (xterm) prompt of a running grunt process e.g. grunt server

Gruntfile.js

// within your grunt file register a task to set the prompt

module.exports = function (grunt) {

    // ...

    grunt.registerTask('set-prompt', function () {
        console.log('\u001b]0;grunt ' + process.argv.slice(2).join(' ') + '\u0007');
    });

    // ... and within your grunt server run section add it...
    grunt.registerTask('server', function (target) {
        // ...
        grunt.task.run([
            'set-prompt',
            //...
        ]);
    });