Tether

A local mailbox so Claude, Grok, Gemini, and Codex can leave work for each other.

This repository has two versions. Use one. Do not mix them.

Version	Where	What
Rust (current)	main	This tree. One binary, SQLite, five MCP tools.
Python (frozen)	branch python, tag legacy-python-v2.1.13, zip legacy-python-v2.1.13.zip	v2.1.13 dashboard / Konsole / FastAPI. For history or rebase.

SQLite is the bus. There is no daemon, no dashboard, and no terminal injection. A message is a row with a unique id. Identical text sent twice is two messages.

cargo install --path .
tether on
tether send --from grok claude "look at this" "mailbox is up"
tether inbox claude
tether recv <id>

tether off writes a sentinel next to the database. Every command and MCP tool then fails closed.

MCP

Point every agent at the same database and a distinct name:

{
  "mcpServers": {
    "tether": {
      "command": "tether",
      "args": ["mcp"],
      "env": {
        "TETHER_AGENT_ID": "grok",
        "TETHER_DB": "$HOME/.local/share/tether/mailbox.db"
      }
    }
  }
}

Five tools: tether_send, tether_inbox, tether_recv, tether_ack, tether_who.

Default database: $XDG_DATA_HOME/tether/mailbox.db (usually ~/.local/share/tether/mailbox.db). This is a new file. It does not touch postoffice.db.

Commands

tether send [--from NAME] [--thread T] TO SUBJECT [BODY...]
tether inbox [--all] [AGENT]
tether recv [--wait] [--timeout SECS] [ID|FROM]
tether ack ID
tether who
tether status
tether on
tether off
tether mcp

--from and the inbox agent default to TETHER_AGENT_ID. There is no default name of unknown.

Test

cargo test

cargo test is the kernel. cargo test --test prove is two processes on one file. The live drill and the stop-rules are in docs/guides/verify.md.

Wake hooks (optional, not TUI injection): docs/guides/wake.md.

The Python product lives on the python branch.