Quickstart

This walks through your first live switch, from Codex to Claude Code and back.

1. Check your setup

constant doctor
constant status

doctor confirms the agent CLIs and session stores are present. status shows runtime readiness, your latest sessions, and the current trail.

2. Host an agent

constant host codex

You are now in a normal Codex session, running inside Constant. Talk to it as usual. Everything looks and behaves like Codex, because it is Codex.

3. Switch the runtime

The default prefix is Ctrl-B. Press Ctrl-B, release, then c:

Ctrl-B c

Codex stops and Claude Code resumes the same conversation, in the same directory. Your next message continues the thread; you do not re-explain anything. Press Ctrl-B then x to hand it back to Codex.

See Keybindings for the full set.

4. See what Constant did

constant trail
constant route

trail shows the current Constant projection per runtime for this directory. route is the debug view that reconstructs the fork graph with readable aliases like codex[1] and claude[1.1].

Already inside tmux?

Ctrl-B is also tmux's prefix. Pick another one:

constant host codex --prefix C-t
CONSTANT_PREFIX=C-t constant host codex

Next: Hosting a runtime.