Claude, Codex and Pi
assist runs agents in a coding harness: Claude Code, the Codex CLI or pi. Claude is the default, and the others work wherever they’re installed.
Setting up Codex and pi
Section titled “Setting up Codex and pi”Install the harness, then run assist sync. It installs assist’s slash commands into each harness it finds on your PATH, and the hooks that let read-only commands run without asking.
Codex asks you to trust assist’s hook the first time it runs on a machine.
Choosing a harness
Section titled “Choosing a harness”The New session dialog’s prompt mode, a backlog item’s Build and Refine, each have a menu that runs them with Codex or with pi instead. On the CLI, --harness <claude|codex|pi> does the same for assist refine and assist backlog run.
To use another harness by default, set harness.engine:
assist config set harness.engine codexHiding a harness
Section titled “Hiding a harness”The with Codex and with pi menu entries show whenever that harness is installed. To hide them, turn the harness’s key off:
assist config set harness.exposeCodexActions falseassist config set harness.exposePiActions falseTo run Codex on a model served by your own proxy, see LiteLLM.