Update Learning Hub for recent Copilot CLI/app changes

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

website/src/content/docs/learning-hub/understanding-mcp-servers.md

@@ -3,7 +3,7 @@ title: 'Understanding MCP Servers'
 description: 'Learn how Model Context Protocol servers extend GitHub Copilot with access to external tools, databases, and APIs.'
 authors:
   - GitHub Copilot Learning Hub Team
-lastUpdated: 2026-07-13
+lastUpdated: 2026-08-30
 estimatedReadingTime: '8 minutes'
 tags:
   - mcp
@@ -213,6 +213,10 @@ Some MCP servers require authentication to connect to protected resources. GitHu
 
 > **Tip**: If your MCP server uses OAuth with Dynamic Client Registration but hosts its authorization metadata at a non-standard URL (as some enterprise servers like Atlassian Rovo do), Copilot CLI handles this automatically.
 
+> **Windows Entra ID broker sign-in** *(v1.0.81+)*: On Windows, remote MCP servers protected by Microsoft Entra ID can now sign in through the OS authentication broker (WAM), usually with no prompt at all. Other platforms, the `--device-code` flag, and machines without the broker library continue to use the existing browser-based flow.
+
+> **MCP spec support** *(v1.0.81+)*: Copilot CLI, the SDK, IDE integrations, and in-memory clients now support the **MCP 2026-07-28** specification revision, keeping pace with the latest protocol capabilities.
+
 ## How Agents Use MCP Tools
 
 When an agent declares an MCP server in its `tools` array, Copilot can invoke that server's capabilities during conversation: