EAI endpoint: admin/passwords ?

I was poking around the Twitter app, and noticed that its setup.xml utilizes an admin/passwords endpoint to, I believe, store and retrieve twitter credentials:

From the setup.xml

    <block title="Add Twitter Account Info" endpoint="admin/passwords" entity="_new">
            <input field="name">
                    <label>Username</label>
                    <type>text</type>
            </input>
            <input field="password">
                    <label>Password</label>
                    <type>password</type>
            </input>
    </block>

From the scripted input:

def getCredentials(sessionKey):
   try:
      entities = entity.getEntities(['admin', 'passwords'], namespace='twitter', owner='nobody', sessionKey=sessionKey) 
   except Exception, e:
      sys.stderr.write("Could not get Twitter credentials from splunk. Error: %s" % (str(e)))
      exit(1)

   for i, c in entities.items(): 
        return c['username'], c['clear_password']

I'm quite intrigued. I could use this functionality, but I can't find any documentation on what it's actually doing or how to use it properly. In particular, I have a need to potentially store multiple sets of credentials, so I'd be curious whether that's possible. Where can I find some docs on this?