Nexus CLI

Connect Claude Code, ChatGPT, Codex, Cursor IDE, VS Code, Copilot, and more to Fireworks with one Nexus CLI command, and undo it with one more.

Nexus CLI is an open-source command-line tool that connects your coding harness to Fireworks models.

• It rewrites your harness settings to call Fireworks.
• It adds Nexus Auto to the harness’s model picker.
• It restores your original settings when you turn it off.

Nexus CLI was formerly FireConnect. If you still use FireConnect, run fireconnect upgrade once to upgrade.

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Quick start

1. Install and sign in

   curl -fsSL https://nexus.fireworks.ai/install.sh | bash
   

   You need Node.js 22 or later, git, and bash. On Windows, run the installer from Git Bash. PowerShell breaks the script’s line endings.

   nexus login
   

   Sign in with your browser, or paste a Fireworks API key (fw_...).

2. Connect a harness

   nexus claude
   

   Replace claude with your harness:

   Harness	Command
   Claude Code, Claude Agent SDK	nexus claude
   Claude Desktop	nexus claude-desktop on
   Codex CLI	nexus codex
   ChatGPT desktop app	nexus chatgpt
   OpenCode	nexus opencode
   Pi	nexus pi
   DeepSeek Harness	nexus deepseek
   Cursor IDE	nexus cursor
   VS Code	nexus vscode
   Copilot App	nexus copilot-app
   Copilot CLI	nexus copilot-cli

   Quit desktop apps before you connect them or run off, then reopen them: Cursor IDE, VS Code, the Copilot App, the ChatGPT and Codex apps, and Claude Desktop. A running app can save over the new settings or keep showing the old models.

3. Restart and check

   Restart the harness, or start a new session. Then run nexus claude status (use your harness name). It shows the provider, where the key comes from, and the configured model.

To undo, run nexus <harness> off. To configure a harness yourself, follow Manual setup.

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Connect and restore

• nexus <harness> connects a harness and saves a snapshot of its settings.
• nexus <harness> off restores your original settings.
• nexus status lists every harness and whether it’s connected.
• nexus update updates Nexus CLI and your connected harnesses. Restart each harness it names.

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Choose a model

Connecting starts the harness on auto. On Enterprise, use --model to add or select a specific model, then restart the harness:

nexus opencode --model glm-latest

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MCP servers and web search

• MCP servers are unchanged, and nexus <harness> off leaves them in place. The exception is Claude Desktop, which manages them as connectors.
• Tool search stays on, so large MCP tool sets load on demand.
• Web search works through Fireworks in Claude Code, Claude Desktop, Codex, and the ChatGPT desktop app without additional configuration.

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Upgrading from earlier versions

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Upgrading from FireConnect

Run fireconnect upgrade once, or re-run the installer. Your command, settings, and connected harnesses move to Nexus CLI.

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Per harness

Harness	If you connected with	Run
Codex, ChatGPT desktop app	FireConnect 0.9.9 or earlier	nexus update, then restart Codex or reopen the app
DeepSeek Harness	FireConnect before 0.9.8	nexus deepseek once
OpenCode	An earlier version, with OpenCode v2’s providers map	nexus update
Claude Code	FireConnect before 0.9.7	nexus update