MCP-Terminal-Bridge

TerminalBridge

Headless yet Powerful

An MCP (Model Context Protocol) server that enables AI assistants to seamlessly control and interact with terminal/TUI applications.

Overview

This server acts as a bridge between AI assistants (like Claude) and terminal applications, providing:

• Terminal application launching with PTY emulation
• Visual output capture with ANSI support
• Keyboard input simulation
• Terminal state information

Current Implementation Status

Phase 1: Foundation (COMPLETE ✅)

• ✅ All 9 MCP tools implemented and working
• ✅ Session management with automatic cleanup
• ✅ PTY wrapper for terminal control
• ✅ Screen buffer with basic ANSI support
• ✅ Special key mapping (arrows, function keys, Ctrl sequences)
• ✅ Multiple output formats (plain, raw, ansi)
• ✅ Concurrent session support
• ✅ Build system with Makefile

Phase 2: Core Features (COMPLETE ✅)

• ✅ Enhanced ANSI parser (supports CSI, SGR, OSC, DCS, and more)
• ✅ Terminal resize support with SIGWINCH handling
• ✅ Structured logging throughout
• ✅ Scrollback buffer support (1000 lines)
• ✅ All unit tests passing
• ✅ Proper renderRaw() with ANSI sequences
• ✅ Multiple output formats including scrollback

Phase 3: Testing & Robustness (IN PROGRESS 🚧)

• ✅ Comprehensive integration test framework
• ✅ Tests for all 9 MCP tools
• ✅ Test applications (echo, menu, progress)
• ✅ 13 out of 18 integration tests passing
• 🚧 Error recovery and session management
• 🚧 Performance optimizations

Quick Start

# Install dependencies
go mod download

# Build the server
make build

# Build test applications
make test-apps

# Run the server (stdio mode)
./bin/terminalbridge

# Or run directly
go run cmd/server/main.go

# Run tests
make test

# Test with example app (in another terminal)
cd test/apps
./echo

MCP Tools

launch_app

Launch a new terminal application.

{
  "command": "vim",
  "args": ["test.txt"],
  "env": {"TERM": "xterm-256color"}
}

view_screen

Get the current terminal content.

{
  "session_id": "session-123",
  "format": "plain"  // or "raw", "ansi", "scrollback"
}

Output formats:

• plain: Text only, no ANSI escape sequences
• raw: Full terminal output with ANSI escape sequences
• ansi: Debug format showing cursor position with ▮
• scrollback: Includes scrollback buffer history

send_keys

Send keyboard input to the terminal.

{
  "session_id": "session-123",
  "keys": "Hello World"  // or "Enter", "Ctrl+C", etc.
}

Other Tools

• get_cursor_position: Get current cursor position
• get_screen_size: Get terminal dimensions
• resize_terminal: Resize the terminal window
• restart_app: Restart a session
• stop_app: Terminate a session
• list_sessions: List all active sessions

Configuration

Environment variables:

• MCP_PORT: Not used in current stdio implementation
• MAX_SESSIONS: Maximum concurrent sessions (default: 100)
• SESSION_TIMEOUT: Idle timeout in minutes (default: 30)
• LOG_LEVEL: Logging level (default: info)

Implementation Notes

• Uses mark3labs/mcp-go v0.31.0 for MCP protocol
• Uses creack/pty v1.1.24 for terminal emulation
• Runs in stdio mode (standard input/output)
• Session cleanup runs every 5 minutes
• Default terminal size: 80x24 (resizable via resize_terminal tool)
• Structured JSON logging to stderr (configurable via LOG_LEVEL)
• Enhanced ANSI parser supports most common escape sequences

Development

See project.md for complete technical design and progress.md for current development status.

Testing

# Run all tests
make test

# Run with coverage
make test-coverage

# Run integration tests
make test-integration

# Run specific test suites
make test-terminal    # Terminal package tests
make test-session     # Session manager tests

License

MIT