Codex is OpenAI’s AI coding assistant, available as a command-line tool and as a VS Code extension. You can connect Codex to the ScitiX Model Inference API and use ScitiX models for coding tasks. Both the CLI and the extension share the same config.toml.
Configuration is stored in config.toml in your Codex home directory, typically ~/.codex/config.toml. For the full list of options, see the Codex Configuration Reference.
Supported models include glm-5.2 and kimi-k2.6. For model pricing, see the model catalog.
1. Install Codex
For the CLI, install Codex with npm or Homebrew:
For other installation options, see the official installation guide.
For the VS Code extension:
- Open Extensions in VS Code (
Ctrl+Shift+X / Cmd+Shift+X).
- Search for Codex and install the official extension.
- Click the Codex icon in the top-right of the editor to open the CODEX panel.
Create an API Key on the API Keys page, then provide it in one of two ways.
Keep SCITIX_API_KEY and other secrets out of Git. Use environment variables or a local .env file ignored by version control.
Option 1: Use an environment variable
Edit ~/.codex/config.toml with env_key pointing to an environment variable:
Set the key before launching Codex:
Option 2: Store the token in config.toml
If you do not want to use an environment variable, put the key directly in config.toml with experimental_bearer_token instead of env_key.
Because the key is stored in the file, keep config.toml out of version control.
Either way, the configured model becomes available in Codex.
Field Reference
MCP Servers
Some built-in tool types, such as web_search, may not be available on these models. You can add these capabilities through MCP (Model Context Protocol) servers.
Configure a search MCP server in config.toml under [mcp_servers.<name>], and Codex will call it when web search is needed. See the Codex Configuration Reference for MCP server setup details.