Run Codex, OpenAI's agentic coding CLI, on Upstage
Solar models. A single script points Codex at the Upstage API and launches it โ your existing
~/.codex settings are left untouched.
Install
Run the one-line setup:
On first run the script reads your Upstage API key, verifies it with a test call, and launches Codex on Solar. It installs nothing without your confirmation.
Prerequisites
- Upstage API key โ create one in the Upstage Console.
- Codex CLI installed. See OpenAI's installation guide.
What the script does
Finds your API key
Reads your key from the UPSTAGE_API_KEY environment variable, your saved credentials, or a
one-time masked prompt โ then verifies it before launch.
The key is only ever sent to https://api.upstage.ai.
Stores it securely (optional)
If you opt in, the key is saved to your OS secret store โ macOS Keychain or Linux Secret Service โ or a permission-locked file. Answer no and nothing is stored.
Launches Codex on Solar
Starts Codex against Upstage Solar (default model: solar-pro4) and registers the Solar models so
you can switch model or reasoning effort mid-session. The Solar settings apply only to that Codex
session.
Useful commands
The first run offers to install the script to ~/.local/bin as codex-solar. Once installed
you can use its subcommands:
Inside a session, /model lets you switch between the registered Solar models and their reasoning
effort.
What you can do next
With Codex running on Solar, you can drive your codebase through natural-language commands:
- Automate routine tasks โ write, refactor, and fix code across your project.
- Understand code โ ask Codex to explain complex or unfamiliar code.
- Handle git workflows โ stage changes, write commit messages, and open pull requests.