How to use the @salesforce/command.flags.help function in @salesforce/command

import {flags, SfdxCommand} from '@salesforce/command';
import {ClusterPackager} from '../../../lib/clusterPackager';
import { FileWriter } from '../../../lib/fileWriter';
import {Member, PackageMerger} from '../../../lib/packageMerger';

export default class PackageMerging extends SfdxCommand {

  public static description = 'This tool allows you to merge several package.xmls together to create one base package.xml.' +
  'You can put the file names (including paths) to the package.xmls as args (as many as you want) and the base package.xml will be outputted to the console.';

  public static strict = false;

  public static flagsConfig = {
    help: flags.help({char: 'h', description: 'get some help'}),
    outputdirectory: flags.string({char: 'd', description: 'output folder location to put package.xml'})
    // flag with no value (-f, --force)
  };

  public async run(): Promise {

    const fileArray = new Array>();
    let cont = false;
    for (const file of this.argv) {
      if (file === '-d' || file === '--outputdir') { // TODO: Find a better way to get args and flags
        cont = true; // Skip next arg also
        continue;
      }
      if (cont) {
        cont = false;
        continue;