Add privacy and data handling section to Fern Writer page (#4323)

Co-authored-by: fern-support <support@buildwithfern.com>
Co-authored-by: bot_apk <apk@cognition.ai>
Co-authored-by: Devin Logan <devinannlogan@gmail.com>
Co-authored-by: fern-api[bot] <115122769+fern-api[bot]@users.noreply.github.com>

Author: 4 people

fern/products/docs/pages/ai/writer.mdx

@@ -11,7 +11,7 @@ Fern Writer is a Slack-based technical writing agent that keeps your docs aligne
 
 ### Making a request
 
-In Slack channels where you've added Fern Writer, tag `@Fern Writer` and describe the change you need. Fern Writer only responds when directly tagged. It will react to your message to confirm receipt, then create a pull request and reply with a link.
+In Slack channels where you've added Fern Writer, tag `@Fern Writer` and describe the change you need. Fern Writer [only responds when directly tagged](#privacy-and-data-handling). It will react to your message to confirm receipt, then create a pull request and reply with a link.
 
 Fern Writer supports image and file attachments for additional context. When tagged in an existing thread, it reads the full conversation to understand context before responding.
 
@@ -52,7 +52,7 @@ Each pull request includes a **Requested by** field in the description, attribut
 ## Setup
 
 <Info>
-    Fern Writer only supports GitHub. GitLab and other Git providers aren't currently supported.
+    Fern Writer only supports GitHub. GitLab and other Git providers aren't supported.
 </Info>
 
 To start using Fern Writer, add it to your Slack workspace (you must be a Slack admin) and invite it to channels where your team discusses documentation.
@@ -84,3 +84,9 @@ Once installed, add Fern Writer to Slack channels where your team discusses docu
 
 </Step>
 </Steps>
+
+## Privacy and data handling
+
+Fern Writer doesn't store your Slack messages directly. When you tag `@Fern Writer` or reference a message or thread, the content is stored in a session to generate the documentation pull request. Session data isn't retained after the task completes.
+
+Neither Fern nor [Devin](https://docs.devin.ai/admin/security#how-is-your-data-used-to-improve-devin) uses your data to train AI models. Fern explicitly configures its Devin integration to opt out of any data collection for model training. Your channel messages, code, and documentation content are never used for training purposes. See Devin's documentation on [Slack integration security](https://docs.devin.ai/admin/security#integrating-with-slack) for additional details.