Merge pull request #6598 from sdgilley/patch-25

Update prompt-flow.md

Author: prmerger-automator[bot]

articles/ai-foundry/concepts/prompt-flow.md

@@ -7,6 +7,7 @@ ms.custom:
   - ignite-2023
   - build-2024
   - ignite-2024
+  - hub-only
 ms.topic: concept-article
 ms.date: 06/30/2025
 ms.reviewer: none
@@ -24,6 +25,8 @@ Prompt flow is a development tool designed to streamline the entire development
 
 Prompt flow is available independently as an open-source project on [GitHub](https://github.com/microsoft/promptflow), with its own SDK and [VS Code extension](https://marketplace.visualstudio.com/items?itemName=prompt-flow.prompt-flow). Prompt flow is also available and recommended to use as a feature within both [Azure AI Foundry](https://ai.azure.com/?cid=learnDocs) and [Azure Machine Learning studio](https://ml.azure.com). This set of documentation focuses on prompt flow in Azure AI Foundry portal.
 
+[!INCLUDE [hub-only-prereq](../includes/uses-hub-only.md)]
+
 Definitions:
 
 - *Prompt flow* is a feature that can be used to generate, customize, or run a flow.