CodexHost

Per its README, an add-on that lets other agent harnesses (Pi, Claude Code, Grok Build and ten-plus others) run inside the Codex Desktop window, so they get Codex’s native diff view, fork, message editing and slash commands, and can collaborate with each other.

• Maker: BytePioneer-AI (GitHub; team size not stated, README bilingual English/Chinese). No company note exists.
• Licence / cost: LGPL-3.0, free and open source; the README solicits sponsorship.
• Platforms: macOS (arm64/x64), Windows (x64/arm64), Linux (x64/ARM64); install via npm install -g @codexhost/cli or installer.
• How it works: patches/hosts Codex Desktop, so it depends on the Codex Desktop app being installed and may break when Codex updates (inference; the README has a console and update command). Exact mechanism not verified beyond that.
• Harnesses: Pi, Oh My Pi, Claude Code, Grok Build and others (feature matrix lists 13 columns).
• Maturity: very new: repo created 2026-07-24, v0.12.1 on 2026-10-03, about 2.7k stars at check time.
• Versus similar tools: per the README it extends Codex’s own UI rather than being a standalone app; the comparison with Synara, Waku and MonoCode (author’s reading, not verified) is that those are standalone.

Open items

• Whether OpenAI permits this approach under Codex Desktop terms: not checked.
• Full harness list not enumerated.

Sources (fetched 2026-10-05)

• https://github.com/BytePioneer-AI/codex-host (README, releases, metadata via GitHub API)