{"servers":[{"server":{"$schema":"https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json","name":"io.github.dovahkiin-v/letterbox","description":"File-based comms protocol for AI-to-AI dialogue between terminal agents.","title":"Letterbox","repository":{"url":"https://github.com/dovahkiin-v/letterbox","source":"github"},"version":"1.2.2","packages":[{"registryType":"pypi","identifier":"letterbox","version":"1.2.2","transport":{"type":"stdio"},"environmentVariables":[{"description":"Channel name to open. Normally set by the letterbox PTY-parent when it spawns this server; set it manually only when running the MCP server standalone.","isRequired":true,"format":"string","name":"LETTERBOX_CHANNEL"},{"description":"This endpoint's identity on the channel — the name the peer agent sees on every message.","isRequired":true,"format":"string","name":"LETTERBOX_SENDER"},{"description":"Per-launch instance id, the watcher/own-write join key that stops an agent seeing its own messages as incoming. Must be unique per launch.","isRequired":true,"format":"string","name":"LETTERBOX_INSTANCE_ID"}]}]},"_meta":{"io.modelcontextprotocol.registry/official":{"status":"active","statusChangedAt":"2026-08-24T22:33:12.843311Z","publishedAt":"2026-08-24T22:33:12.843311Z","updatedAt":"2026-08-24T22:33:12.843311Z","isLatest":true}}}],"metadata":{"count":1}}