Persistent Shell MCP

This is experimental software intended for testing and development purposes only. Do not use in production environments or with sensitive data.

A Model Context Protocol (MCP) server that provides persistent shell execution through tmux sessions. This server enables AI assistants to execute commands in a persistent shell. This unlocks a lot of possiblities, such as Agent Orchestration...

Features

• Dual-Window Architecture: Each workspace has two windows - exec for command execution and ui for clean output display

• Persistent Workspaces: Execute commands in tmux sessions that persist across MCP client restarts

• Interactive Process Support: Handle long-running processes, REPLs, and interactive commands

• Workspace Isolation: Multiple isolated workspaces for different projects or tasks

• Clean UI Management: Separate windows for execution and user-facing output

• Automatic Session Management: Create, destroy, and monitor workspaces seamlessly

Installation

🚨 SECURITY WARNING: This software allows AI assistants to execute arbitrary shell commands on your system. Only install and use in isolated testing environments. Never use on systems with sensitive data or in production environments.

Prerequisites

• Node.js 18.0.0 or higher

• tmux installed on your system

  • Ubuntu/Debian: sudo apt install tmux

  • macOS: brew install tmux

  • CentOS/RHEL: sudo yum install tmux

Install from npm

npm install -g tmux-mcp-server

Install from source

git clone https://github.com/TNTisdial/persistent-shell-mcp.git
cd persistent-shell-mcp
npm install
npm link

Usage

MCP Client Configuration

Add to your MCP client configuration:

{
  "mcpServers": {
    "tmux-shell": {
      "command": "tmux-mcp-server"
    }
  }
}

Available Tools

Core Execution Tools

execute_command

Execute commands that complete quickly and return full output. Uses the exec window.

execute_command({
  command: "ls -la", 
  workspace_id: "my-project"
})

start_process

Start long-running or interactive processes. Can target either window:

• exec window (default): For background processes

• ui window: For interactive applications that need user visibility

start_process({
  command: "python3", 
  workspace_id: "dev",
  target_window: "ui"  // For interactive apps like vim, python REPL
})

get_output

Capture current terminal output from either window:

• ui window (default): Clean user-facing output

• exec window: Raw shell with all commands

get_output({
  workspace_id: "dev",
  window_name: "ui"  // or "exec" for raw output
})

send_input

Send input to running processes in either window.

send_input({
  text: "print('Hello World')", 
  workspace_id: "dev",
  target_window: "ui"
})

stop_process

Stop the currently running process in the exec window (sends Ctrl+C).

stop_process({workspace_id: "dev"})

Workspace Management Tools

create_workspace

Create a new isolated workspace with dual windows.

destroy_workspace

Destroy a workspace and all its processes.

list_workspaces

List all active workspaces.

Architecture

Dual-Window Design

Each workspace consists of two tmux windows:

1. exec: Raw shell for command execution

   • Handles all command execution

   • Shows full shell history and prompts

   • Used for background processes

2. ui: Clean output display

   • Shows clean output for user interaction

   • Used for interactive applications

   • Provides better user experience

Workspace Isolation

• Each workspace is a separate tmux session

• Independent working directories and environments

• Processes don't interfere between workspaces

• Clean separation of different projects/tasks

Common Workflows

Quick Command Execution

// Execute and get results immediately
execute_command({command: "npm install", workspace_id: "frontend"})
execute_command({command: "git status", workspace_id: "frontend"})

Interactive Development

// Start Python REPL in UI window
start_process({
  command: "python3", 
  workspace_id: "python-dev",
  target_window: "ui"
})

// Send Python commands
send_input({text: "import os", workspace_id: "python-dev", target_window: "ui"})
send_input({text: "print(os.getcwd())", workspace_id: "python-dev", target_window: "ui"})

// Check output
get_output({workspace_id: "python-dev", window_name: "ui"})

Background Process Management

// Start server in background
start_process({command: "npm run dev", workspace_id: "server"})

// Check server status
get_output({workspace_id: "server", window_name: "exec"})

// Stop server when done
stop_process({workspace_id: "server"})

Multi-Project Development

// Frontend workspace
create_workspace({workspace_id: "frontend"})
execute_command({command: "cd /path/to/frontend", workspace_id: "frontend"})

// Backend workspace  
create_workspace({workspace_id: "backend"})
execute_command({command: "cd /path/to/backend", workspace_id: "backend"})

// Database workspace
create_workspace({workspace_id: "database"})
start_process({command: "mysql -u root -p", workspace_id: "database", target_window: "ui"})

Project Structure

tmux-mcp/
├── src/
│   ├── server.js          # Main MCP server and tool definitions
│   ├── tmux-manager.js    # Tmux session and window management
│   └── index.js           # Entry point
├── bin/
│   └── tmux-mcp-server    # Executable script
├── package.json
└── README.md

Troubleshooting

Tmux Not Found

Error: tmux command not found

Install tmux: sudo apt install tmux (Ubuntu/Debian) or brew install tmux (macOS)

Workspace Creation Failed

Error: Failed to create workspace

Check if tmux server is running and you have permissions to create sessions

Commands Not Responding

Check workspace status with get_output

Use get_output with window_name: "exec" to see raw shell state

Process Stuck

Use stop_process to send Ctrl+C

Send interrupt signal with stop_process to terminate hanging processes

License

MIT