The T3 Code alternative you can change without forking

Both are free, MIT-licensed apps that run Claude Code, Codex, and other coding agents in Git worktrees on your own machines, with mobile and remote access, and both let agents hand work to each other. bb is built to be changed: install a plugin from the marketplace or have an agent build one, instead of keeping a fork. And in bb, every agent another agent starts is a full thread you can open and message mid-run. bb is also fully scriptable: its CLI and SDK can drive anything the app does.

Yes: bb. It’s free for any team size and MIT-licensed, so you can use and change it for anything, including at work. Plugins add whatever you need without forking, and your agents work together across providers. Download bb.

Ask bb to do it. T3 Code keeps each thread’s worktree as plain Git on your machine, in ~/.t3/worktrees, so a bb agent can add your repos and open each unfinished worktree as a thread. Your CLAUDE.md, skills, MCP servers, and agent sign-ins come along, and T3 Code keeps working while you try bb.

• When you want a new panel, command, or agent, you install or build a plugin instead of patching the app.
• When an agent starts another, the new one is a full thread you can message.
• Several threads can share one worktree, so a reviewer works right next to the agent that wrote the code.
• Setup commands from t3.json move to .bb-env-setup.sh, and untracked files like .env go in .worktreeinclude.

Yes. bb works out of the box, with worktrees, diff review, automations, and the mobile app ready from your first thread. When you want more, install plugins from the marketplace or ask an agent to build one. Plugins can add panels, commands, and new agents, and they work in the mobile app too.

Yes. The bb CLI covers everything the app does: start and message threads, run terminals, schedule automations, and manage machines and plugins, so a script or another agent can drive bb end to end. The SDK and plugin API let you add your own commands, tools, and screens. T3 Code’s CLI mostly installs and runs its server, and outside agents can start and message threads through its MCP server.

Yes. bb reads each agent’s own skills and slash commands and shows them in that agent’s / menu, so the ones you use today keep working.

1. Download bb for macOS (Apple Silicon), Windows, or Linux (both alpha). On an Intel Mac, run npx bb-app@latest, which needs Node.js 22.19 or later.
2. Install and sign in to a coding agent, like Claude Code, Codex, Cursor, or OpenCode.
3. Open bb, add your project folder, and type your first request.

Claude Code, Codex, Cursor, and OpenCode, plus Pi, Grok Build, omp, and Hermes Agent. In Settings, add any other agent that supports the Agent Client Protocol (ACP), an open standard for connecting coding agents to apps, like Gemini CLI or Devin. You can also add one with a plugin. Each thread can use a different agent.

Yes. Ask Claude Code to “start a bb Codex thread to review this branch, then fix what it finds.” It starts Codex in the same worktree, waits, and applies the fixes. Codex shows up as its own thread, so you can read the exact prompt Claude sent, watch it work, and message it mid-run. Any other pair works the same way, like Cursor and OpenCode.

bb picks the work back up. When an agent stops on a usage limit that reports when it resets, bb sends the message again a little after the reset, so you don’t have to come back and press send. To keep going on another Claude Code or Codex account you own, turn on Account Pooler, a plugin built into bb. T3 Code shows your accounts’ limits, but you switch accounts yourself.

Yes. Pick a permission mode for each thread. Accept Edits applies changes inside the project and asks before anything else. Approve for me reviews requests automatically and sends high-risk ones to you. Full Access skips approvals and can run anything on your machine. Allow or deny approvals from your computer or your phone.

Yes. Commit a .bb-env-setup.sh at your repo root and bb runs it in every new worktree. List untracked files like .env in .worktreeinclude and bb copies them in first, and .bb-env-teardown.sh cleans up when a worktree goes away.

Yes, without leaving the thread. Select lines in its diff and choose Add to chat to send feedback. Once the agent opens a pull request, the thread shows its checks and a Merge button. The GitHub plugin adds Review with agent to any PR.

bb lets you rewind the conversation instead. Edit any earlier message to rerun the thread from there, or fork a new thread from any message to try a different approach. In a worktree thread, changes stay on that thread’s branch until you merge them.

Yes, for free. Use the bb mobile app, a public beta on iPhone through TestFlight (Apple’s beta testing app) and in alpha on Android, or open bb in any browser through bb Connect, bb’s free remote access.

Yes, free. Automations start an agent thread or run a script on a repeating schedule, once at a set time, or after a delay. Pick the agent, model, and permission mode, and give each run its own worktree if you like.

Yes, for one person or a whole team. The mobile app, remote machines, automations, and plugins are all included. You pay only for the agent plans or API keys you already use, from any provider. The code is on GitHub under the MIT license.

Yes. bb runs the agents you already use, signed in the way you already pay for them: a Claude Pro or Max plan, a ChatGPT plan for Codex, a Cursor plan, API keys, or any other provider’s plan. Your existing setup comes along too (CLAUDE.md, skills, MCP servers, and agent settings).

Yes. Download the app for Apple Silicon Macs, Windows, or Linux (both alpha), or run npx bb-app@latest on an Intel Mac.

Yes: bb runs on your machines, so your code goes only where your agents send it, the AI providers you chose. Anonymous usage stats exclude code and prompts and can be turned off. The bb Connect relay doesn’t store traffic, but isn’t end-to-end encrypted.

Yes, free at any team size. Teams can share one bb on an always-on machine, so everyone sees the same projects and threads, or each person can run their own and share work through Git as usual. bb doesn’t offer team plans, SSO, or a support SLA.