Pty MCP Server

What is pty-mcp-server?

pty-mcp-server is a Haskell implementation of the Model Context Protocol (MCP) that enables AI agents to acquire and control pseudo-terminal (PTY) connections dynamically. It communicates with MCP clients exclusively via stdio, allowing AI to interact with external CLI-based tools in a structured, automated way.

How to use pty-mcp-server?

Install with cabal install pty-mcp-server, then run with pty-mcp-server -y config.yaml. The server is typically launched by development tools like Visual Studio Code via a .vscode/mcp.json configuration. The config.yaml file specifies logging, script directories, and prompt detection strings.

Key features of pty-mcp-server

• Launches commands through PTY interfaces with optional arguments
• Provides tools for interactive Bash, SSH, cabal, stack, and GHCi sessions
• Supports scriptable CLI integration via tools-list.json and shell scripts
• Dynamically resolves tools by name without recompilation
• Operates exclusively in stdio transport mode
• Follows a modular, onion-architecture package design

Use cases of pty-mcp-server

• Performing interactive REPL operations (e.g., GHCi) for Haskell development
• Interactive debugging of Haskell applications
• System diagnostics through bash scripting
• Remote server management via SSH
• Dynamic execution of CLI tools in PTY environments