Samples from Pivotal Tracker's webhook

note_create

<?xml version="1.0" encoding="UTF-8"?>
<activity>
  <id type="integer">160540935</id>
  <version type="integer">276</version>
  <event_type>note_create</event_type>
  <occurred_at type="datetime">2012/02/10 18:35:54 UTC</occurred_at>
  <author>Jori Lallo</author>
  <project_id type="integer">76939</project_id>
  <description>Jori Lallo added comment: &quot;Woot&quot;</description>
  <stories type="array">
    <story>
      <id type="integer">13550905</id>
      <url>http://www.pivotaltracker.com/services/v3/projects/76939/stories/13550905</url>
      <notes type="array">
        <note>
          <id type="integer">18506253</id>
          <text>Woot</text>
        </note>
      </notes>
    </story>
  </stories>
</activity>

story_create

<activity>
  <id type="integer">160541171</id>
  <version type="integer">277</version>
  <event_type>story_create</event_type>
  <occurred_at type="datetime">2012/02/10 18:36:25 UTC</occurred_at>
  <author>Jori Lallo</author>
  <project_id type="integer">76939</project_id>
  <description>Jori Lallo added &quot;Add integration to Grove&quot;</description>
  <stories type="array">
    <story>
      <id type="integer">24778015</id>
      <url>http://www.pivotaltracker.com/services/v3/projects/76939/stories/24778015</url>
      <name>Add integration to Grove</name>
      <story_type>feature</story_type>
      <current_state>unscheduled</current_state>
      <requested_by>Jori Lallo</requested_by>
    </story>
  </stories>
</activity>

story_update

<?xml version="1.0" encoding="UTF-8"?>
<activity>
  <id type="integer">160540717</id>
  <version type="integer">275</version>
  <event_type>story_update</event_type>
  <occurred_at type="datetime">2012/02/10 18:35:26 UTC</occurred_at>
  <author>Jori Lallo</author>
  <project_id type="integer">76939</project_id>
  <description>Jori Lallo started &quot;Shop browsing views could have more shops (or see all)&quot;</description>
  <stories type="array">
    <story>
      <id type="integer">13550905</id>
      <url>http://www.pivotaltracker.com/services/v3/projects/76939/stories/13550905</url>
      <current_state>started</current_state>
    </story>
  </stories>
</activity>