Codex Desktop Setup

The OpenAI Codex desktop app can sign in with an API key and open the user-level config.toml from inside the app. The API key entered on the sign-in screen only gets you into the app; to send requests through Aiberm, you must also configure the Aiberm provider and API key in config.toml.

Prerequisites

Before you begin, make sure you have:

• The latest OpenAI Codex desktop app
• An Aiberm account (Sign up)
• An Aiberm API key (Create one in Console)

Configuration

1. Open the Codex desktop app.
2. On the sign-in screen, choose Sign in another way.

3. Enter your Aiberm API key in the OpenAI API key field, then choose Continue.

Note: this step only gets you into the Codex desktop app. It does not replace the API key configuration in config.toml. You must complete the configuration below even if you already entered a key on the sign-in screen.

4. After entering the app, open Settings.
5. Select Configuration in the sidebar.
6. Under Custom config.toml settings, make sure User config is selected.
7. Choose Open config.toml to open the user-level config file.

8. Add or replace the contents of config.toml with the following configuration.

Before editing, remove any old [model_providers.aiberm] block from the file to avoid duplicate settings. TOML settings must use one line per item; do not put multiple settings on the same line.

Put the API key directly in config.toml

Put the API key directly in config.toml:

model = "gpt-5.6-sol"
model_provider = "aiberm"
model_reasoning_effort = "xhigh"

[model_providers.aiberm]
name = "Aiberm API"
base_url = "https://aiberm.com/v1"
experimental_bearer_token = "sk-your-aiberm-api-key"
wire_api = "responses"
supports_websockets = false

Writing the API key directly stores it in plain text on your computer. Make sure this file is not committed to Git or shared with anyone else.

If this is your first time configuring Codex, replace sk-your-aiberm-api-key with your real Aiberm API key and make sure the file is saved.

9. Save config.toml.
10. Fully quit and reopen the Codex desktop app.

Verify It Works

After reopening Codex:

1. Open a project or workspace.
2. Ask Codex to perform a real coding task, such as explaining the current file, editing a small piece of code, or running project tests.

If the task runs and returns a result, the configuration is working.

Troubleshooting

Invalid API Key

• Copy the full key from Aiberm Console.
• Check for extra spaces before or after the key.
• Confirm the key starts with sk-.

Configuration Changes Do Not Apply

• Confirm you edited the config.toml opened from User config.
• Fully quit and reopen the Codex desktop app after saving the file.
• Confirm model_provider = "aiberm" matches [model_providers.aiberm].
• Confirm experimental_bearer_token was replaced with your real Aiberm API key and the placeholder sk-your-aiberm-api-key was not saved unchanged.

TOML Format Errors

• Put each setting on its own line. For example, wire_api and supports_websockets must not share one line.
• Use straight double quotes for string values, such as model = "gpt-5.6-sol".
• Set base_url directly to https://aiberm.com/v1; do not use Markdown link syntax or add extra brackets.

Model or Connection Errors

• Confirm the base_url is exactly https://aiberm.com/v1.
• Confirm wire_api is responses.
• Confirm your account can access gpt-5.6-sol. For the current list, see Models List.

Official Reference

• OpenAI Codex: Configuration Reference