Copilot coding agent failing to start n8n MCP server

[simonknittel]

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Copilot Coding Agent

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I'm trying to set up the n8n MCP server (https://github.com/czlonkowski/n8n-mcp) for the Copilot coding agent. I've already got it successfully working locally in VSCode with Copilot, but I'm having issues with the Copilot coding agent on GitHub.

I've added this MCP configuration to the Copilot coding agent in my repository:

{
	"mcpServers": {
		"n8n-mcp": {
			"type": "local",
			"command": "npx",
			"args": [
				"-y",
				"n8n-mcp"
			],
			"env": {
				"MCP_MODE": "stdio",
				"LOG_LEVEL": "error",
				"DISABLE_CONSOLE_OUTPUT": "true",
				"N8N_API_URL": "https://<my self-hosted n8n instance>",
				"N8N_API_KEY": "COPILOT_MCP_N8N_API_KEY"
			},
			"tools": ["*"]
		}
	}
}

I've also added the n8n API key as environment secret (COPILOT_MCP_N8N_API_KEY) in the copilot environment in that repository.

I've also added the n8n API URL to the Custom allowlist of the Copilot coding agent firewall in that repository.

Now, when I prompt the Copilot coding agent I'm getting the following error when it tries to start the MCP servers:

MCP server failed to start: MCP error -32001: Request timed out - for the full output, see the verbose logs

Looking at the verbose/detailed logs shows this:

Starting MCP servers...
Waiting for MCP servers to be ready...
MCP servers not ready yet. Retrying in 1 second... (1/60)
MCP servers not ready yet. Retrying in 1 second... (2/60)
MCP servers not ready yet. Retrying in 1 second... (3/60)
MCP servers not ready yet. Retrying in 1 second... (4/60)
MCP servers not ready yet. Retrying in 1 second... (5/60)
MCP servers not ready yet. Retrying in 1 second... (6/60)
MCP servers not ready yet. Retrying in 1 second... (7/60)
MCP servers not ready yet. Retrying in 1 second... (8/60)
MCP servers not ready yet. Retrying in 1 second... (9/60)
MCP servers not ready yet. Retrying in 1 second... (10/60)
MCP servers not ready yet. Retrying in 1 second... (11/60)
MCP servers not ready yet. Retrying in 1 second... (12/60)
MCP servers not ready yet. Retrying in 1 second... (13/60)
MCP servers not ready yet. Retrying in 1 second... (14/60)
MCP servers not ready yet. Retrying in 1 second... (15/60)
MCP servers not ready yet. Retrying in 1 second... (16/60)
MCP servers not ready yet. Retrying in 1 second... (17/60)
MCP servers not ready yet. Retrying in 1 second... (18/60)
MCP servers not ready yet. Retrying in 1 second... (19/60)
MCP servers not ready yet. Retrying in 1 second... (20/60)
MCP servers not ready yet. Retrying in 1 second... (21/60)
MCP servers not ready yet. Retrying in 1 second... (22/60)
MCP servers not ready yet. Retrying in 1 second... (23/60)
MCP servers not ready yet. Retrying in 1 second... (24/60)
MCP servers not ready yet. Retrying in 1 second... (25/60)
MCP servers not ready yet. Retrying in 1 second... (26/60)
MCP servers not ready yet. Retrying in 1 second... (27/60)
MCP servers not ready yet. Retrying in 1 second... (28/60)
MCP servers not ready yet. Retrying in 1 second... (29/60)
MCP servers not ready yet. Retrying in 1 second... (30/60)
MCP servers not ready yet. Retrying in 1 second... (31/60)
MCP servers not ready yet. Retrying in 1 second... (32/60)
MCP servers not ready yet. Retrying in 1 second... (33/60)
MCP servers not ready yet. Retrying in 1 second... (34/60)
MCP servers not ready yet. Retrying in 1 second... (35/60)
MCP servers not ready yet. Retrying in 1 second... (36/60)
MCP servers not ready yet. Retrying in 1 second... (37/60)
MCP servers not ready yet. Retrying in 1 second... (38/60)
MCP servers not ready yet. Retrying in 1 second... (39/60)
MCP servers not ready yet. Retrying in 1 second... (40/60)
MCP servers not ready yet. Retrying in 1 second... (41/60)
MCP servers not ready yet. Retrying in 1 second... (42/60)
MCP servers not ready yet. Retrying in 1 second... (43/60)
MCP servers not ready yet. Retrying in 1 second... (44/60)
MCP servers not ready yet. Retrying in 1 second... (45/60)
MCP servers not ready yet. Retrying in 1 second... (46/60)
MCP servers not ready yet. Retrying in 1 second... (47/60)
MCP servers not ready yet. Retrying in 1 second... (48/60)
MCP servers not ready yet. Retrying in 1 second... (49/60)
MCP servers not ready yet. Retrying in 1 second... (50/60)
MCP servers not ready yet. Retrying in 1 second... (51/60)
MCP servers not ready yet. Retrying in 1 second... (52/60)
MCP servers not ready yet. Retrying in 1 second... (53/60)
MCP servers not ready yet. Retrying in 1 second... (54/60)
MCP servers not ready yet. Retrying in 1 second... (55/60)
MCP servers not ready yet. Retrying in 1 second... (56/60)
MCP servers not ready yet. Retrying in 1 second... (57/60)
MCP servers not ready yet. Retrying in 1 second... (58/60)
MCP servers not ready yet. Retrying in 1 second... (59/60)
MCP servers not ready yet. Retrying in 1 second... (60/60)
Failed to start MCP servers after 60 attempts
Ending MCP step

I already tried disabling the Copilot coding agent firewall fully. This didn't change anything.

Any idea what is missing or wrong?