/node_modules/keystone/admin/client/App/screens/Item/index.js

{(this.props.params.listId === 'my-list-model') ? (
    <MyComponent>{this.props.params.listId}</MyComponent>
) : null }

import keystone from 'keystone';
import { someFunction } from './myFunctions';

var MyListModel = new keystone.List('MyListModel', {
   map: { name: 'title' },
});

MyListModel.add({
   title: { type: String, required: true },
   data: { type: Types.Code, language: 'json', watch: 'title', value: watchTitle, noedit: true },
});

MyListModel.register();


function watchTitle(callback) {
    if (this.title) {
        function cb(error, result) {
            if (result) {
                // Send result to React Component in Admin screen
            }
            callback(error, result);
        }
        someFunction(this.title, cb);
    } else {
        callback(null, '');
    }
}