title: What is `build agent folder` $(SourceDir) of a build definition in TFS Build 2012?
body: <p>When creating a <code>build definition</code> for a TFS build, there is a section called <code>Source Settings</code> as below snapshoot where we have to define 1) Source Control Folder and 2) Build Agent Folder.</p>
  
  <p>As I understand, the <code>source control folder</code> is where to get the source to build. But I don't get the idea what is the <code>build agent folder</code> is used for in a build.</p>
  
  <p>Please share me what that is about if you know it. Thank you!</p>
  
  <p><img src="https://i.stack.imgur.com/moTtU.png" alt="enter image description here"></p>