added tool asset description

Author: ms-johnalex

articles/ai-foundry/how-to/develop/vs-code-agents.md

@@ -126,7 +126,10 @@ Add a tool to the AI Agent with the following steps:
     :::image type="content" source="../../media/how-to/get-started-projects-vs-code/agent-openapi-tool-dialog.png" alt-text="Screenshot of the OpenAPI 3.0 Specified tool dialog box." lightbox="../../media/how-to/get-started-projects-vs-code/agent-openapi-tool-dialog.png":::
 
     1. After entering the required information, select the **Upload and save** button in the bottom-left corner.
-        
+ 
+> [!NOTE]
+> When you add a tool, you can also add any new assets it needs. For example, if you add a File Search tool, you can use an existing vector store asset or make a new asset for your vector store to host your uploaded files.
+
 ### Create Azure AI Agents on the Azure AI Foundry Studio
 
 Create your agent directly on Azure AI Foundry with the following steps: