Codex Integration with RezeAI Tutorial

Codex is a powerful coding agent tool that supports reading, modifying, and running project code in the terminal (CLI) or VS Code.

This article will guide you through seamlessly switching your Codex underlying model to RezeAI by customizing the Provider and ensuring compatibility with OpenAI Responses.

I. Preparations Before Integration (3 Core Elements)

Before starting the configuration, please clarify the following 3 core parameters, which will be frequently used in subsequent configurations:

| Configuration Items | Recommended Content | Notes |

| :--- | :--- | :--- |

| API Key | sk-xxxxxxxxxxxxxxxx | Please enter the plain text key directly |

II. Quick Integration Guide

Step 1: Install Codex CLI

Please ensure that Node.js is installed on your computer.

If your environment does not have Node.js, click to download

Open a terminal and run the following command to install it globally:

Step 2: Create a Configuration File (config.toml)

Codex officially recommends defining custom Providers using a config.toml file.

Locate or create the configuration directory:

Windows: C:\Users\Your Username.codex

macOS / Linux: ~/.codex

Create a file named config.toml in this directory.

Paste the following content completely and save:

# Basic Configuration
model_provider = "RezeAI"
model = "Please replace with the actual model name supported by RezeAI"
preferred_auth_method = "apikey"
disable_response_storage = true

# RezeAI Custom Provider Configuration

[model_providers.rezeai]
name = "RezeAI"
base_url = "https://api.rezeai.com/v1"
env_key = "REZEAI_API_KEY"
wire_api = "responses"

Parameter Explanation: This configuration directly specifies the API gateway (base_url) and tells Codex to retrieve the password from the system's REZEAI_API_KEY environment variable.

Step 3: Configure the API Key Environment Variable

For security, please do not write the API Key directly in the configuration file. Please inject the environment variable in the terminal using the following command, depending on your operating system:

Windows PowerShell (temporarily applies to the current window):

$env:REZEAI_API_KEY="sk-your RezeAI key"

Windows PowerShell (permanently writes to user variables, requires terminal restart):

[System.Environment]::SetEnvironmentVariable("REZEAI_API_KEY", "sk-your RezeAI key", "User")

macOS / Linux:

Step 4: Startup and Testing

After configuration, navigate to any of your project's code directories using the terminal and run:

After startup, try entering a simple read-only analysis command, such as: Please summarize the main module structure of the current repository. If Codex responds and outputs results correctly, congratulations, your RezeAI integration is complete!

III. Using the Extension in VS Code

Codex's CLI terminal version and IDE extension share the same underlying configuration.

Once you've completed the config.toml and environment variable configurations mentioned above, you can directly search for and install the Codex plugin from the VS Code extension store. It's ready to use out of the box, without any additional tedious configuration in VS Code.

IV. Troubleshooting Common Issues (FAQ)

Q1: Authentication Failed after startup?

Check if your terminal environment variable REZEAI_API_KEY is set successfully. If you are using Windows' permanent write command, you must completely close and reopen the terminal for it to take effect.

Check if you accidentally added the Bearer prefix to the key you entered.

Q2: Model Not Found after startup? **

The model field in the config.toml file cannot be filled in arbitrarily. Please strictly refer to the list of available models provided in the RezeAI console and fill in the complete name without any errors.

Q3: The connection is established, but the experience is unstable and errors occur frequently?

Codex's Provider strongly depends on the responses interface. If instability occurs under high concurrency or special network environments, please ensure that wire_api = "responses" in config.toml is spelled correctly and check whether the currently selected model is fully compatible with OpenAI's Responses specification.**

Codex

Codex Integration with RezeAI Tutorial#

I. Preparations Before Integration (3 Core Elements)#

II. Quick Integration Guide#

Step 1: Install Codex CLI#

Step 2: Create a Configuration File (config.toml)#

Step 3: Configure the API Key Environment Variable#

Step 4: Startup and Testing#

III. Using the Extension in VS Code#

IV. Troubleshooting Common Issues (FAQ)#