I converted Rex to an AI Harness
I use Rex all day with Claude Code (sometimes Codex) running in a pane, and the thing that kept bugging me was the loop around the agent. It finishes a turn, and then I'm running git diff in another pane, opening files to see what it actually did, and typing "in brew.ts line 13, change X" back into the chat.
So I hacked together a mod for Rex. It adds a panel on the right that shows what the agent changed in its last turn, and it updates live while the agent is working. It also has uncommitted and branch diffs, plus a file tree. Click a file and it opens in Neovim next to the agent, on the line that changed. If something looks off, hit Space r on the line and write a note. The note goes to the agent with your next message, along with the code it's about. That's pretty much the whole idea, and the video shows it better than I can explain it.
A few other things ended up in there. There's a ⌘P file finder. When you open a file in a new language, the editor installs its language server for you. And it works with Codex, OpenCode and Pi, not just Claude Code.
Fair warning: this isn't official. To get a panel into Rex I had to patch the app and re-sign it locally. Because of that, Rex can't update itself anymore, so rexmod checks for new Rex releases, verifies them and patches them itself. There's an uninstaller that puts the original app back.
If you want to try it (Apple silicon, macOS 15+):
brew trust --tap alpcanaydin/rexmod
brew install alpcanaydin/rexmod/rexmod
rexmod-setup
Code's here: alpcanaydin/rexmod
It's early, so I'd love to hear what breaks, especially from anyone using Codex, OpenCode or Pi day to day.
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Turn Superlogical's Rex into an AI Harness
@Covenantlabsai @superlogical Shipped it now with github.com/alpcanaydin/rexmod/releases/tag/v0.1.6 ✌️
I converted Rex to an AI Harness I use Rex all day with Claude Code (sometimes Codex) running in a pane, and the thing that kept bugging me was the loop around the agent. It finishes a turn, and then I'm running git diff in another pane, opening files to see what it actually did, and typing "in brew.ts line 13, change X" back into the chat. So I hacked together a mod for Rex. It adds a panel on the right that shows what the agent changed in its last turn, and it updates live while the agent is working. It also has uncommitted and branch diffs, plus a file tree. Click a file and it opens in Neovim next to the agent, on the line that changed. If something looks off, hit Space r on the line and write a note. The note goes to the agent with your next message, along with the code it's about. That's pretty much the whole idea, and the video shows it better than I can explain it. A few other things ended up in there. There's a ⌘P file finder. When you open a file in a new language, the editor installs its language server for you. And it works with Codex, OpenCode and Pi, not just Claude Code. Fair warning: this isn't official. To get a panel into Rex I had to patch the app and re-sign it locally. Because of that, Rex can't update itself anymore, so rexmod checks for new Rex releases, verifies them and patches them itself. There's an uninstaller that puts the original app back. If you want to try it (Apple silicon, macOS 15+): brew trust --tap alpcanaydin/rexmod brew install alpcanaydin/rexmod/rexmod rexmod-setup Code's here: alpcanaydin/rexmod It's early, so I'd love to hear what breaks, especially from anyone using Codex, OpenCode or Pi day to day.