title: Resetting or overwriting the lifespan of a context in DialogFlow
body: <p>I'm trying to manage the context of my Google Assistant agent (in DialogFlow), using the ApiAi class in the npm package <code>actions-on-google</code>.</p>
  
  <p>The problem is this:
  How can I reset the lifespan / delete a context using the npm package?</p>
  
  <p>I can easily set the lifespan of a new context, and it works.</p>
  
  <p>However:</p>
  
  <ol>
  <li>How do I delete a context?</li>
  <li>Setting the context to a different number does not seem to work. That is, if I set <code>app.setContext('myContext',10)</code> and then, 2 intents later, when the lifespan in <code>8</code>, I call <code>app.setContext('myContext',10)</code> again, in the next intent, the lifespan is still <code>7</code>. If I could answer (1) and delete a context, I'd just delete it and set it again.</li>
  </ol>