added a step in kb to prompt the asssitant before publishing (#265)

Author: ramsrib

fern/knowledge-base/knowledge-base.mdx

@@ -68,9 +68,16 @@ There are two main approaches to creating a Knowledge Base in Vapi:
 
 #### **Step 3: Publish the Assistant**
 
-1. Review your assistant configuration to ensure all settings are correct
-2. Click the "Publish" button to make your changes live
-3. This automatically creates a default knowledge base (using the query tool) with the selected files for the assistant
+1. Instruct your assistant to use the knowledge base when relevant by adding appropriate prompts in your assistant's configuration. This helps ensure the assistant knows when to reference the knowledge base versus using its general knowledge.
+
+   For example, if you have a knowledge base about your company's products, you might add this prompt:
+   ```
+   When users ask about our products, services, or company information, use the knowledge base to provide accurate details.
+   ```
+
+2. Review your assistant configuration to ensure all settings are correct
+3. Click the "Publish" button to make your changes live
+4. This automatically creates a default knowledge base (using the query tool) with the selected files for the assistant
 
 <Note>
   When you publish an assistant with selected files, Vapi automatically creates