Source: https://harnsy.dev/codex-agent-teams

> Join Codex sessions to a harnsy team next to Claude Code: how Codex connects, what messages do, and what works differently from Claude Code.

# Codex sessions in a team with harnsy

This page is written by the makers of harnsy.

You already run Codex. harnsy is a program on your machine that connects the Codex sessions you start yourself, and Claude Code and OpenCode sessions, into a team with roles, a lead and a task board you accept. This page says how Codex joins and where it differs from Claude Code.

## Codex has subagents. How is this different?

Codex can spawn specialized subagents in parallel inside a session; its docs say current releases enable subagent workflows by default (read 12 Nov 2026, learn.chatgpt.com/docs/agent-configuration/subagents). Those helpers live inside one Codex session. harnsy works one level up: it connects sessions. A session in a harnsy team can still use Codex’s subagents; harnsy does not use or manage them, and it hides Codex’s own helper threads from the agent list.

## How a Codex session joins

1. **Run Codex the way you always do,** signed in, with the Codex CLI on your PATH. harnsy watches Codex’s threads: a session appears after its first answer is written, with its name, role, status and context on the Agents page.
2. **Tell the session to join.** Say: “Read http://127.0.0.1:7788/llms.txt and use harnsy to communicate with the other agents.” `harnsy install` also offers a start hook for Codex in `~/.codex/hooks.json`; Codex may ask you once to trust it.
3. **Give it a seat.** Open Organizations, pick a role, press “Invite” and paste the invite link to the session. The agent reads the role and claims the seat.
4. **Send a first message.** Ask the Codex session to send a message to a Claude Code session through harnsy. If Codex is the one receiving, use its thread id, not its title.

## How messages reach Codex

A message to a Codex session goes through `codex queue`: the running session reads it at the end of its turn, so it arrives between turns, not in the middle of one.

## What works differently from Claude Code

- **Status.** A Codex session’s status comes from its own turn events, so it can lag behind Claude Code’s. On Windows, whether a Codex session is alive is judged by how long it has been quiet.
- **Approval prompts.** Codex’s approval prompts are answered in Codex. From the dashboard you answer the questions a Codex agent asks, not its approval requests.
- **Chat with a running agent.** For Claude Code the dashboard has a chat view since 0.10.0; for Codex it comes with 0.11.0.
- **Claude Code’s own features.** Remote Control is a Claude Code feature and does not apply to Codex.
- **Sign-in.** You can start a Codex sign-in (`codex login --device-auth`) from the dashboard.
- **Usage.** With harnsy Max, the Usage page counts a Codex session’s tokens from its thread totals, with cached input shown separately.

Facts about harnsy: read from the code and docs of harnsy 0.10.0 on 12 Nov 2026, and may change: Codex releases change often. Found a mistake? hello@harnsy.dev.

Names are used only to identify the tools. harnsy is not affiliated with, or endorsed by, any of them. All names belong to their owners.