[Feature] Add Model Context Protocol (MCP) Server

[J0EK3R]

A few days ago, I read a very interesting article about AI and the Model Context Protocol (MCP).

This gave rise to the idea of extending BC2 with the capabilities of an MCP server.

The MCP server would (like the game controller does) simply control channels in BC2 with the values (-1..0..1).

That would be pretty cool – you could use the app in an educational setting to get closer to the topic of AI.

The setting could be:

• Claude's desktop app
• MCP server that integrates a USB camera that films overhead a playing field with a model car
• BC2 with the MCP server to control the model car

You could then give the AI tasks like:

• Drive a circle
• Drive a figure eight
• Drive to the points
• Follow the line

What do you think?

[J0EK3R]

HowTo

I've pushed PR #165 [POC] McpServer for Win.

💡 Tip: If you want to try it out just get my branch feature/MCPServer to your PC and build the Win App...

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Now, if the Brickcontroller2 Win App is started, the McpServer has to be enabled in the settings:

You can change to Port the McpServer is listening on and set a password to protect the server.

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When enabled the McpServer is shown in the Controller tester view as Controller:

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You can test the MCPServer in you Browser by requesting (if no password ist set)

http://localhost:5000/health

or

http://localhost:5000/mcp/capabilities

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To access BC2 by the Claude Desktop App you have to add the (bridge script to connect to the) McpServer in the claude_desktop_config.json like this

{
  "mcpServers": {
    "brickcontroller": {
      "command": "py",
      "args": [
        "C:\\Projects\\brickcontroller2\\BrickController2\\MCPServer\\mcp_http_bridge.py",
        "--url",
        "http://localhost:5000"
        "--token",
        "YOUR_SECRET_TOKEN_HERE"
      ]
    }
  }
}

The bridge script mcp_http_bridge.py is located in the brickcontroller repo.

💡 In a later Release the Claude App would perhaps directly support MCPServers over http without using a wrapper or bride script.

Then just run the Claude Desktop App and start to prompt:

First prompt

list tools

to enshure the brickcontroller MCPServer is available:

Next prompt could be

set channel 1 to 0,5 and channel 2 to -0,99

You'll see the result in the Controller tester:

Next prompt could be

stop all channels

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Next step could be to create a new Creation in BC2 and bind the events to real-life devices:

Press one of the Add-Buttons:

Then you have to prompt something like

set channel 1 to 1 then to 0

💡 Tip: After setting the channel value to 1, you need to make sure that the value is reset to 0 - this is like moving the joystick up on a PS controller and releasing it again

Then define the controller action for the channel event.

Now a real-life device can be controlled by Claude...

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Here is a pretty useless prompt:

every time you start doing something set channel 1 to 1 and when you've finished the task set channel 1 to 0

I understand! From now on, I'll set channel 1 to 1 when I start doing a task, and set it back to 0 when I finish. This will act as an activity indicator.
Let me know what you'd like me to help you with, and I'll follow this pattern with the channel controls.

please do something for 5 seconds

I'll start the task by setting channel 1 to 1, then do something for 5 seconds, then set it back to 0.

...

Done! I performed a 5-second task with channel 1 acting as an activity indicator - it was set to 1 at the start and back to 0 when finished.

[vicocz]

Hi,
still not sure about it whether it's worth implementing it.
I guess the app is intended to be the simplest one. THerefore there is no UI to control the models but just gamepad. From that perspective this adds unnecessary complexity and increase codebase.
On the other hand any AI integration might be interesting to play with. But it would required more inputs IMHO, channel motor telemetry, sensor info, etc. Which is the thing this app is definitely not reeady for. I have long term plans (or better say dreams) to rewrite the app using different framework, but it's too far and too big to implement.

Currently I'm quite busy with preparation for some LEGO exhibition and my priorities related to the app is to have better release process, ideally using the officially stores. Therefore I think there is no chance to invest my time to this feature.

I will reconsider it once thew exhibition is over. ONe possibility is to have some experimental branch, but I guess it's nearly the same as to keep your own fork with this feature.

Regards
Vit

[J0EK3R]

Hello Vit,
Thanks for your open words and for sharing your dreams and plans (for the app) with me! ;)
Yes, the lack of time (for the things you really want) – that's my problem too.

In my opinion, implementing the MCP Server could boost the app and could be very useful, for example, in education to do some experiments with AI – the buzzword AI is ubiquitous and the future – I'm using it more and more for programming.

The impact on the code is very minimal – in simple terms, it's just another controller that triggers events, and the option to enable it in the settings page (and set the port and password).

But it would required more inputs IMHO, channel motor telemetry, sensor info, etc. Which is the thing this app is definitely not reeady for.

In my opinion, it's sufficient to act as a game controller; the AI just using BC2 as bridge to the motors and will do the rest.

Here's my proposal: I'll implement the MCP server for all our platforms and prepare the code for merging.
The impact on the existing codebase will really be minimal.
If you're ready, we'd be happy to discuss it again.

...that's one of my dreams... ;)