This JavaScript file displays the project level fields on the associated Project Site in Project Server 2013 / Project Online. This script will display the following default fields:

It also displays two custom fields:

For the script to work "out of the box" you will need to add those fields to your Project Server / Project Online config, otherwise edit the script to remove those fields and associated code or replace those fields / modify the code with fields of your own. A code snippet can be seen below:

 

JavaScript
Edit|Remove
<script type="text/javascript"> 
 var ProjectUID; 
 ExecuteOrDelayUntilScriptLoaded(getProjectUIDProperty, "sp.js");  
 function getProjectUIDProperty() {  
                var ctx = new SP.ClientContext.get_current();  
                this.web = ctx.get_web(); 
 

Example outputs can be seen below:

 

 

Another image:

 

The blog post below details how to use the script and highlights parts of the script that would need to be edited for your own custom fields etc.

http://pwmather.wordpress.com/2014/06/10/supporting-post-for-projectserver-2013-projectonline-project-fields-displayed-on-project-site-javascript-jquery/