# Codex CLI

Codex CLI provides OpenAI model access for general security analysis and code-oriented workflows.

## Requirements

* `codex` CLI installed.
* `OPENAI_API_KEY` available in the Burp runtime environment.

## Setup

1. Install CLI:

```bash
npm install -g @openai/codex
```

2. Export API key:

```bash
export OPENAI_API_KEY="sk-..."
```

3. Verify locally:

```bash
codex "hello"
```

4. Configure in **AI Backend** settings tab.

## Configuration

| Setting               | Value                  |
| --------------------- | ---------------------- |
| **Preferred Backend** | `Codex CLI`            |
| **Codex CLI Command** | `codex chat` (default) |

Model example:

```bash
codex --model gpt-5.2
```

## Notes

### Windows

The extension automatically resolves npm-installed CLI shims on Windows. When `codex` is configured, the resolver:

1. Checks for a `.cmd` sibling next to the resolved path (e.g., `codex.cmd` alongside `codex`).
2. Falls back to wrapping the command with `cmd /c` if no `.cmd` sibling is found.

This prevents `CreateProcess error=193` that occurs when Java tries to execute a shell script shim directly on Windows.

{% hint style="info" %}
You do not need to manually specify `.cmd` extensions. The extension handles this automatically for all npm-installed CLI backends.
{% endhint %}

### Windows + WSL bridge

If Burp runs on Windows and Codex runs in WSL, set **Codex CLI Command** to a `.cmd` wrapper that forwards args into WSL.

Wrapper example:

```bat
@echo off
setlocal
wsl.exe -d Ubuntu -- script -q -c "bash -lc 'codex %*'" /dev/null 2>nul | findstr /V /R /C:"^OpenAI Codex v" /C:"^--------" /C:"^workdir:" /C:"^model:" /C:"^provider:" /C:"^approval:" /C:"^sandbox:" /C:"^reasoning" /C:"^session id:" /C:"^user$" /C:"^mcp startup:" /C:"^thinking$"
exit /b %ERRORLEVEL%
```

## Troubleshooting

{% hint style="info" %}

* `command not found`: use full binary path or npm shim path.
* Windows: npm shim paths are resolved automatically. If auto-resolution fails, use the full `.cmd` path: `C:\\Users\\<you>\\AppData\\Roaming\\npm\\codex.cmd`.
* Auth errors: verify `OPENAI_API_KEY` in Burp runtime env.
* Rate limits: check provider quota/tier.
  {% endhint %}

## Related Pages

* [Backends Overview](/backends/overview.md)
* [Troubleshooting](/reference/troubleshooting.md)


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://burp-ai-agent.six2dez.com/backends/codex-cli.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.