hcom

hcom is a Rust-based terminal-level multi-agent collaboration tool positioned as a communication and orchestration middleware among coding agents. Rather than replacing any AI agent, it connects coding agents such as Claude Code, Gemini CLI, Codex, and OpenCode into a unified SQLite message bus through automatically injected hooks, enabling cross-terminal real-time messaging, context handoff, and event subscription.

In terms of collaboration capabilities, hcom supports agents viewing each other's transcripts, file edits, terminal screens, and command history. A built-in collision detection mechanism automatically alerts both agents when two agents edit the same file within 30 seconds. It also provides full lifecycle management — spawning, forking, resuming, or terminating agents across terminals. Message delivery is adapted for mainstream coding agents: messages are injected mid-turn between tool calls, or idle agents are woken immediately.

For distributed scenarios, hcom provides relay functionality based on the MQTT protocol, supporting token-authenticated agent networks across different machines. The project is open-sourced under the MIT license, distributed via Homebrew and PyPI, currently in Beta (v0.7.13), and available on macOS and Linux. The repository also includes Claude Code plugin and Gemini CLI extension definitions to lower the barrier to entry.

Installation

# Homebrew (recommended)
brew install aannoo/hcom/hcom
# PyPI
pip install hcom

Quick Start

# Terminal 1
hcom claude
# Terminal 2
hcom codex
# Open TUI management interface
hcom

Core CLI Commands

• hcom <agent_name>: Launch agent with prefix (e.g., claude, codex, gemini, opencode)
• hcom: Open TUI management interface
• hcom start: Join other AI tools to the hcom network
• hcom send: Send messages to agents from any process
• hcom status: Output diagnostic information
• hcom reset all: Clear and archive database, hooks, and config
• hcom hooks remove: Safely remove all hcom hooks
• hcom config terminal --info: View custom terminal configuration
• hcom run docs: Tell agent about runtime docs
• hcom relay new / hcom relay connect <token> / hcom relay status / hcom relay on|off: Cross-device relay management

Environment Variables

• HCOM_DIR: Custom hooks and config directory (default: ~/)

Architecture Highlights

• Message mechanism: agent → hooks → db (SQLite) → hooks → other agent
• Hooks are auto-installed on first run with zero side effects when hcom is not in use
• Cross-device communication based on MQTT protocol
• Repository includes .claude-plugin, plugin/hcom, skills/hcom-agent-messaging, gemini-extension.json and other plugin/extension definitions