# Run Claude Code and Codex together in Herdr

Set up two terminal panes, give Claude a small build and have Codex review it against the same written brief. The download includes the reading-list brief, a review prompt and the finished example from Luke’s test.

[HTML](https://lukejbyrne.com/library/guides/ibm8oz045dw/)
Content language: en
Author: Luke Byrne
Video published: null
Guide published: 2026-11-08

[Watch the video](https://www.youtube.com/shorts/ibM8OZ045Dw)
Video language: English

- [Download the reading-list exercise](https://lukejbyrne.com/library/downloads/herdr-reading-list.zip)

[Complete guide](https://lukejbyrne.com/library/guides/otx_eew2c0c/index.md)

## Install Herdr and open a project

On a Mac with Homebrew, run the commands below from a new scratch directory. For other systems, follow the TUI installation link. Claude Code and Codex each need their own installed, signed-in CLI. Check any proposed changes to their configuration during first-run setup.

1. brew install herdr
2. herdr --version
3. herdr
4. Start Claude Code in one pane. Press Ctrl+B, release, then V to split the view. Launch Codex in the second pane. If Codex asks you to trust a folder, check the path against the scratch directory before approving it.

## Give the two agents different jobs

Unzip the kit and copy requirements.txt into the scratch directory. Ask Claude to implement those requirements in index.html. Keep the example in its separate folder so you can try the build yourself. To let Claude coordinate the second pane, run herdr --skill, add the printed instructions through Claude’s project or skill settings, and run Claude inside Herdr.

1. Ask Codex to review index.html against requirements.txt, describe any specific mismatch and leave the files untouched. Claude can then read the response from the other pane. In Luke’s Herdr v0.9.5 run, Codex reported no concrete issues. A separate browser-DOM test checked adding a book, toggling read status, filtering, restoring after reload and rejecting blank entries.

## Detach and return

Press Ctrl+B, release, then Q to detach. Run herdr again to reconnect while the server is running. After a machine restart the original terminal processes have ended. The session-restore documentation lists what can be recovered. Use the agent list to find a waiting pane and read its output before treating a task as finished.

1. Open example/index.html in your browser. Add a book, mark it as read, filter the list and reload to check that the state persists.

## The takeaway

Keep the brief and the implementation in the same folder so both agents can check the same requirements.

## Workflow resources

- [herdr.dev](https://herdr.dev/tui/docs/install/)
- [herdr.dev](https://herdr.dev/tui/docs/agent-skill/)
- [herdr.dev](https://herdr.dev/tui/docs/session-state/)
- [youtube.com](https://www.youtube.com/watch?v=9_FzA-J9S2E)

## Sources and limitations

Tested on macOS with Herdr v0.9.5. Each agent uses its own account and permissions.

[Original video](https://www.youtube.com/shorts/ibM8OZ045Dw)