How to enable Codex remote control with only the Codex CLI and no ChatGPT app

Codex remote control lets you send instructions from your phone to Codex running on your home PC while you're away. To use remote control, you usually need to keep the ChatGPT app running on your PC.

The ChatGPT app has excellent overall quality, but I ran into an issue where my entire PC became much less responsive after I opened the app or launched a project. I ended up uninstalling the ChatGPT app.

You can use a hidden flag to start remote control with the Codex CLI alone, without installing the ChatGPT app.

Command to start remote control from the Codex CLI

Run the following command to start remote control from the Codex CLI.

codex app-server --remote-control --listen off

This command keeps running, so leave the terminal where you started it open for as long as you want to use remote control. You can then control Codex from the ChatGPT mobile app without installing the ChatGPT app on your PC.

Some articles say you can start remote control with codex remote-control, but this command produced an error on Windows.

$ codex remote-control
Starting app-server daemon with remote control enabled...
Error: codex app-server daemon lifecycle is only supported on Unix platforms

Pairing with only the Codex CLI

Before you can use the remote control command above, you need to pair remote control with the ChatGPT app.

You can pair from the CLI with codex remote-control pair, but this command also fails on Windows with the error Error: codex app-server daemon lifecycle is only supported on Unix platforms.

On Windows, run the following command in PowerShell to generate a pairing code. On the pairing screen in the ChatGPT mobile app, select "Pair manually" and enter the pairing code.

$psi = [Diagnostics.ProcessStartInfo]::new(
    "cmd.exe",
    '/d /s /c "codex app-server --remote-control"'
)
$psi.UseShellExecute = $false
$psi.RedirectStandardInput = $true
$psi.RedirectStandardOutput = $true
$p = [Diagnostics.Process]::Start($psi)

$p.StandardInput.WriteLine('{"id":1,"method":"initialize","params":{"clientInfo":{"name":"codex_remote_pair","title":"Codex Remote Pair","version":"1.0"},"capabilities":{"experimentalApi":true}}}')
do { $r = $p.StandardOutput.ReadLine() | ConvertFrom-Json } until ($r.id -eq 1)

$p.StandardInput.WriteLine('{"method":"initialized"}')
$p.StandardInput.WriteLine('{"id":2,"method":"remoteControl/pairing/start","params":{"manualCode":true}}')
$p.StandardInput.Flush()

do { $r = $p.StandardOutput.ReadLine() | ConvertFrom-Json } until ($r.id -eq 2)
$r.result.manualPairingCode