Update Smart AI Reply docs (#118)

* add setting info

* response -> reply

smart-ai-replies.mdx

@@ -8,16 +8,18 @@ title: 'Smart AI Replies'
   shared Slack channel.
 </Info>
 
-Smart AI Responses allows you to generate responses to support requests based on your documentation and the contents of a thread.
+Smart AI Replies allow you to generate replies to support requests based on your documentation and the contents of a thread.
 
 <Frame>![Smart AI Replies](/public/images/smart-ai-replies.png)</Frame>
 
-Responses are not automatically sent, the composer will be populated with the suggested response, which you can either send as is, or edit as you wish.
+Replies are not automatically sent, the composer will be populated with the suggested reply, which you can either send as is, or edit as you wish.
+
+To enable Smart AI Replies go to **Settings** → **Workflow** and toggle the **Smart AI Replies** setting.
 
 All AI features in Plain are opt-in. More information on our use of OpenAI and our data processing
 policies can be found in our DPA.
 
-### Indexing documentation for use with Smart AI Responses
+### Indexing documentation for use with Smart AI Replies
 
 Documentation can be indexed by using the [Plain CLI](https://github.com/team-plain/cli). With it you can index: