TIL: If you're using the `api.githubcopilot.com/mcp` MCP named "all", it doesn't mean you automatically get the `all` toolset; instead, you receive the `default` toolset. To request the toolset named `all`, you must explicitly provide the header: `"X-MCP-Toolsets": "all"`. This behavior is counterintuitive because the URL implies access to all tools, but attempts to call some of them fail without the required header.
https://github.com/github/github-mcp-server/blob/main/docs/remote-server.md#remote-mcp-toolsets





