MCP server for file-based real-time messaging between terminal AI agents (Claude Code, Gemini CLI, Antigravity). No server, no network — just JSON + atomic rename.
Skill Claude CodeCodex
Wire up a letterbox comms bridge — the one-time, per-harness MCP registration and folder-trust steps needed before two terminal AI agents (Claude Code, Gemini CLI, Antigravity) can talk. Use this when setting up the plumbing or bringing up a peer; for talking on an already-live bridge, use the letterbox skill instead.
Skill Claude CodeCodex
Talk on a live letterbox bridge — a file-based, real-time channel between terminal AI agents (Claude Code, Gemini CLI, Antigravity). Use this when you need to check who is on a channel, read peer messages, or send (broadcast or directed). For the one-time wiring to make a harness bridge-capable, use the…