MCP Client authorization

Feature Requests
1

I’d love to integrate my own MCP servers into Home Assistant.

However, currently it’s only possible to add a URL.

Is there any kind of authorization planned, like setting the value of an Authorization header or passing an X-Api-Key or something?

In my specific case, I’d like to connect to my Perplexity MCP server running on a public server outside of the HA cluster.

2

This seems more like a question than a [FR]
Do you know for a fact that this doesn’t already exist?

I highly suggest you change the category at the top to Configuration - Home Assistant Community and add what you’ve already tried, give others a chance to weigh in on this, Someone might know something about it.

3

Neither the config flow supports any other input than the URL, nor is there any hint about working with such authorization headers in the MCP client code. It’s definitely a feature request.

4

I concur. Have been struggling with this for many hours already.

Bottom line:
Some additions to the documentation for how to configure an MCP (SSE) Client are highly appreciated!

Background:
The HA mcp_server documentation instructs the creation of a long-lived access token to be used by the MCP client. And this API_ACCESS_TOKEN must then be entered in the MCP client.

I have tried to set up the suggested Claude Desktop and mcp-proxy, just to test if my (HA) MCP Server is running, but failed miserably on the mcp-proxy part.

Besides, I want to use a n8n “MCP Client (SSE) API” node, which (I believe) can make SSE calls directly to an MCP Server, and therefore should not need an mcp-proxy.

That MCP Client takes 3 parameters:

  1. SSE URL:
    https://<my_ha_server_url>:8123/mcp_server/sse
    (this is specifically mentioned in the documentation)

  2. Messages Post Endpoint:
    https://<my_ha_server_url>:8123/messages
    (educated guess, based on all the documents I read on the subject)

  3. Additional Headers: here I have tried a zillion possibilities, like:
    API_ACCESS_TOKEN=“the long lived access token I generated earlier”
    or only the token and not the label, or without the quotes, etc etc…

Whatever I try, I cannot figure out how to connect to my HA MCP Server from my (n8n) MCP Client, and I keep getting an 401 response (access denied).

5

Thanks for your input, but I’d like to point out that you’re talking about the mcp_server integration but this feature request is about the mcp client integration.

Even though they’re both related to the Model Context Protocol, they’re some distinct implementations.

I actually have added the mcp_server integration in Claude as described in the documentation. JSON snipped from the claude_desktop_config.json:

    "home-assistant": {
      "command": "/Users/my-user-name/.local/bin/mcp-proxy",
      "args": [
        "https://path-to-my-server/mcp_server/sse"
      ],
      "env": {
        "API_ACCESS_TOKEN": "ey..."
      }
    }

For the messages endpoint, it’s /mcp_server/messages (see comment in code).

I hope it helps you with your issue for the mcp_server integration, even though it’s unrelated to this feature request.

Edit: it seems that your n8n problem is also a bug of the node and not of HA itself.

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