Codex CLI

Delegate coding tasks to Codex via the Hermes terminal. Codex is OpenAI's autonomous coding agent CLI.

Prerequisites

• Codex installed: npm install -g @openai/codex
• OpenAI API key configured
• Must run inside a git repository — Codex refuses to run outside one
• Use pty=true in terminal calls — Codex is an interactive terminal app

One-Shot Tasks

terminal(command="codex exec 'Add dark mode toggle to settings'", workdir="~/project", pty=true)

For scratch work (Codex needs a git repo):

terminal(command="cd $(mktemp -d) && git init && codex exec 'Build a snake game in Python'", pty=true)

Background Mode (Long Tasks)

# Start in background with PTY
terminal(command="codex exec --full-auto 'Refactor the auth module'", workdir="~/project", background=true, pty=true)
Returns session_id
Monitor progress

process(action="poll", session_id="")
process(action="log", session_id="")
Send input if Codex asks a question

process(action="submit", session_id="", data="yes")
Kill if needed

process(action="kill", session_id="")

Key Flags

| Flag | Effect |
|------|--------|
| exec "prompt" | One-shot execution, exits when done |
| --full-auto | Sandboxed but auto-approves file changes in workspace |
| --yolo | No sandbox, no approvals (fastest, most dangerous) |

PR Reviews

Clone to a temp directory for safe review:

terminal(command="REVIEW=$(mktemp -d) && git clone https://github.com/user/repo.git $REVIEW && cd $REVIEW && gh pr checkout 42 && codex review --base origin/main", pty=true)

Parallel Issue Fixing with Worktrees

# Create worktrees
terminal(command="git worktree add -b fix/issue-78 /tmp/issue-78 main", workdir="~/project")
terminal(command="git worktree add -b fix/issue-99 /tmp/issue-99 main", workdir="~/project")
Launch Codex in each

terminal(command="codex --yolo exec 'Fix issue #78: . Commit when done.'", workdir="/tmp/issue-78", background=true, pty=true)
terminal(command="codex --yolo exec 'Fix issue #99: . Commit when done.'", workdir="/tmp/issue-99", background=true, pty=true)
Monitor

process(action="list")
After completion, push and create PRs

terminal(command="cd /tmp/issue-78 && git push -u origin fix/issue-78")
terminal(command="gh pr create --repo user/repo --head fix/issue-78 --title 'fix: ...' --body '...'")
Cleanup

terminal(command="git worktree remove /tmp/issue-78", workdir="~/project")

Batch PR Reviews

# Fetch all PR refs
terminal(command="git fetch origin '+refs/pull//head:refs/remotes/origin/pr/'", workdir="~/project")
Review multiple PRs in parallel

terminal(command="codex exec 'Review PR #86. git diff origin/main...origin/pr/86'", workdir="~/project", background=true, pty=true)
terminal(command="codex exec 'Review PR #87. git diff origin/main...origin/pr/87'", workdir="~/project", background=true, pty=true)
Post results

terminal(command="gh pr comment 86 --body ''", workdir="~/project")

Rules

• Always use pty=true — Codex is an interactive terminal app and hangs without a PTY
• Git repo required — Codex won't run outside a git directory. Use mktemp -d && git init for scratch
• Use exec for one-shots — codex exec "prompt" runs and exits cleanly
• --full-auto for building — auto-approves changes within the sandbox
• Background for long tasks — use background=true and monitor with process tool
• Don't interfere — monitor with poll/log, be patient with long-running tasks
• Parallel is fine — run multiple Codex processes at once for batch work