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Claude Desktop

Use Claude's graphical plugin screen for Chat and Cowork. No Terminal is required.

Your Claude plan must support custom plugins. CARBON does not require a testers.ai subscription.

1. Download carbon-claude.zip and keep the ZIP in Downloads.
2. Open Claude Desktop and choose Customize → Plugins.
3. Choose Add plugin → Upload plugin, select carbon-claude.zip, and choose Install.
4. Open your project folder in Cowork, start a new conversation, and ask: Use CARBON Help to assess this project and recommend next steps.

Claude CLI

Use the CARBON marketplace package for a persistent user-wide installation with the complete runtime and all namespaced CARBON skills.

1. Download carbon-claude-marketplace.zip.
2. Extract it to a permanent carbon-claude-marketplace folder.
3. Add that folder as a Claude marketplace and install carbon@carbon-local for your user.
4. Run /carbon:carbon-help. Claude Code registers CARBON as namespaced skills, not unprefixed slash commands.

cd "$HOME/Downloads"
unzip -o carbon-claude-marketplace.zip -d carbon-claude-marketplace
claude plugin marketplace add "$HOME/Downloads/carbon-claude-marketplace"
claude plugin install --scope user carbon@carbon-local
cd "/path/to/your/project"
claude

unzip -o carbon-claude.zip
cd "/path/to/your/project"
claude --plugin-dir "$HOME/Downloads/carbon"

ChatGPT / Codex

Install in the Codex app using its local marketplace. This ZIP is not an upload for an ordinary ChatGPT conversation.

1. Download and extract carbon-codex.zip into a folder named carbon-codex.
2. In Codex, open Plugins → Add marketplace.
3. Choose Local folder and select the extracted carbon-codex directory.
4. Open CARBON, choose Install, start a new task in your project folder, and run $carbon-help.

cd "$HOME/Downloads"
unzip -o carbon-codex.zip -d carbon-codex
codex plugin marketplace add "$HOME/Downloads/carbon-codex"
codex plugin add carbon@carbon-local

Cursor

Connect the complete CARBON runtime through Cursor’s local MCP settings. Keep the extracted folder in a permanent location.

1. Download carbon.plugin and extract it to a permanent carbon folder.
2. Open Cursor's Settings → MCP screen.
3. Add a local stdio server named carbon, command node, with the absolute path to carbon/bin/carbon-mcp.mjs as its argument.
4. Open your project and ask: Use CARBON to test this automatically.

Antigravity

Install the complete bundle so CARBON's runtime, skills, evidence contracts, and MCP server stay together.

1. Download carbon-antigravity.plugin.
2. Extract it into ~/.gemini/config/plugins/carbon.
3. Restart Antigravity and open the folder containing your project context.
4. Ask: Use CARBON to test this automatically. If the plugin surface is unavailable, configure the included bin/carbon-mcp.mjs as a local MCP server.

mkdir -p "$HOME/.gemini/config/plugins/carbon"
unzip carbon-antigravity.plugin -d "$HOME/.gemini/config/plugins/carbon"

Standalone MCP

Connect CARBON to any client that supports local MCP servers. Requires Node.js 22 or newer.

1. Download and extract carbon-mcp.zip to a permanent folder.
2. Open your client's Settings → MCP servers.
3. Add a local stdio server named carbon.
4. Set command to node and the only argument to the absolute path to carbon-mcp/bin/carbon-mcp.mjs.
5. Restart the client or begin a new task.

{
  "mcpServers": {
    "carbon": {
      "command": "node",
      "args": ["/ABSOLUTE/PATH/TO/carbon-mcp/bin/carbon-mcp.mjs"]
    }
  }
}