Python: Agent sample with GitHub MCP tool using pat token auth

[TaoChenOSU]

The hosted agent team is looking for an agent sample with a MCP tool that connects to GitHub using a PAT token.

[giles17]

This sample now exists here: https://github.com/microsoft/agent-framework/blob/main/python/samples/getting_started/mcp/mcp_github_pat.py