Connect AI Agents

MCP/U works with any MCP-compatible AI agent. This guide covers configuration for all supported agents.

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Quick Reference

Agent	Config File	Add Command	Env Field
Claude Desktop	claude_desktop_config.json	N/A (manual)	"env"
Claude Code	.mcp.json	claude mcp add	"env"
Gemini CLI	~/.gemini/settings.json	gemini mcp add	"env"
OpenCode	opencode.json	N/A (manual)	"environment"

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Claude Desktop

Config file locations:

OS	Path
Linux	~/.config/claude/claude_desktop_config.json
macOS	~/Library/Application Support/Claude/claude_desktop_config.json
Windows	%APPDATA%\Claude\claude_desktop_config.json

Serial Connection

{
  "mcpServers": {
    "mcpu": {
      "command": "npx",
      "args": ["mcpu-client"],
      "env": {
        "SERIAL_PORT": "/dev/ttyACM0"
      }
    }
  }
}

WiFi TCP Connection

{
  "mcpServers": {
    "mcpu": {
      "command": "npx",
      "args": ["mcpu-client"],
      "env": {
        "DEVICES": "mydevice:192.168.1.42:3000:tcp"
      }
    }
  }
}

Mixed Serial + TCP

{
  "mcpServers": {
    "mcpu": {
      "command": "npx",
      "args": ["mcpu-client"],
      "env": {
        "DEVICES": "robot:/dev/ttyUSB0:115200,sensor:192.168.1.42:3000:tcp"
      }
    }
  }
}

Tip

After editing the config, restart Claude Desktop to pick up the changes.

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Claude Code

Add via CLI (recommended)

Serial:

claude mcp add mcpu -e SERIAL_PORT=/dev/ttyACM0 -- npx mcpu-client

WiFi TCP:

claude mcp add mcpu -e DEVICES=mydevice:192.168.1.42:3000:tcp -- npx mcpu-client

Multiple devices:

claude mcp add mcpu -e DEVICES=robot:/dev/ttyUSB0:115200,sensor:192.168.1.42:3000:tcp -- npx mcpu-client

Or edit .mcp.json (project-level, shareable with team)

{
  "mcpServers": {
    "mcpu": {
      "command": "npx",
      "args": ["mcpu-client"],
      "env": {
        "SERIAL_PORT": "/dev/ttyACM0"
      }
    }
  }
}

Verify

claude mcp list

Or inside a session: /mcp

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Gemini CLI

Add via CLI (recommended)

Serial:

gemini mcp add -e SERIAL_PORT=/dev/ttyACM0 mcpu npx mcpu-client

WiFi TCP:

gemini mcp add -e DEVICES=mydevice:192.168.1.42:3000:tcp mcpu npx mcpu-client

Or edit ~/.gemini/settings.json

{
  "mcpServers": {
    "mcpu": {
      "command": "npx",
      "args": ["mcpu-client"],
      "env": {
        "SERIAL_PORT": "/dev/ttyACM0"
      }
    }
  }
}

Verify

gemini mcp list

Or inside a session: /mcp

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OpenCode

OpenCode has no CLI add command — edit opencode.json directly.

Serial Connection

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "mcpu": {
      "type": "local",
      "command": ["npx", "-y", "mcpu-client"],
      "enabled": true,
      "environment": {
        "SERIAL_PORT": "/dev/ttyACM0"
      }
    }
  }
}

WiFi TCP Connection

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "mcpu": {
      "type": "local",
      "command": ["npx", "-y", "mcpu-client"],
      "enabled": true,
      "environment": {
        "DEVICES": "mydevice:192.168.1.42:3000:tcp"
      }
    }
  }
}

Caution

OpenCode uses "environment" (not "env") and "command" must be an array, not a string!

Verify

opencode mcp list

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Environment Variables Reference

Variable	Description	Example
SERIAL_PORT	Serial port (single device)	/dev/ttyACM0, COM3
SERIAL_BAUD	Baud rate (default: 115200)	9600
DEVICES	Multi-device config	id:port:baud, id:host:port:tcp

DEVICES Format

Serial: id:port:baud
TCP:    id:host:port:tcp

Examples:

• robot:/dev/ttyUSB0:115200
• sensor:192.168.1.42:3000:tcp
• robot:/dev/ttyUSB0:115200,sensor:192.168.1.42:3000:tcp

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Summary Table

	Serial	WiFi TCP	Multi-Device
Env var	SERIAL_PORT=/dev/ttyACM0	DEVICES=id:IP:port:tcp	DEVICES=a:/dev/ttyUSB0:115200,b:IP:port:tcp
Windows	SERIAL_PORT=COM3	same format	same format

	Claude Desktop	Claude Code	Gemini CLI	OpenCode
Add command	N/A	claude mcp add	gemini mcp add	Manual only
Config file	claude_desktop_config.json	.mcp.json	~/.gemini/settings.json	opencode.json
Env field	"env"	"env"	"env"	"environment"
Command format	string	string	string	array
Verify	Restart app	claude mcp list	gemini mcp list	opencode mcp list

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Next Steps

• Connect via Serial — detailed serial setup
• Connect via WiFi TCP — detailed TCP setup
• Multi-Device Setup — multiple MCUs
• Debug Connection Issues — troubleshootingingtroubleshooting