Codex App

Also known as: Codex GUI · OpenAI Codex app

Codex App: configure a provider for the desktop app; features vary by version.

Published instructions · App version: unverified

Chat, ping, invoke and content-generation examples may send real billable requests. Check the model, balance, rate and minimum before running them. GET /v1/models checks authentication and the catalogue only. Set up environment variables safely

Base URL to paste

OpenAI SDKs generally use a URL ending in /v1; Anthropic SDKs use the root URL. Avoid adding /v1 twice. Protocol compatibility does not guarantee every provider feature.

https://thapi.cloud/v1

Prerequisites

Codex App or CLI has created ~/.codex
STALI_API_KEY in the environment
The api-cli provider is configured in config.toml

Recommended model: gpt-5.6-sol

Quick way — command / config

# 1) Configure as for Codex CLI (API CLI recommended):
api-cli configure codex -m gpt-5.6-sol
export STALI_API_KEY='sk-thapi-...'

# 2) Open Codex App — select provider/model api-cli / gpt-5.6-sol in Settings if available in the UI

# 3) Important file:
#    ~/.codex/config.toml
#    base_url = "https://thapi.cloud/v1"

Where to place file / fill Settings

Filemacos

~/.codex/config.toml

Follow the codex-cli instructions. Reopen Codex App after making changes.

Filelinux

~/.codex/config.toml

Same as macOS.

Filewindows

%USERPROFILE%\.codex\config.toml

Edit the TOML, then restart the app.

Interfaceany

Codex App → Settings → Models / Providers

Select the custom ThAPI provider if listed in the UI; match the model to gpt-5.6-sol.

Verify connection

Send a short chat message in Codex App.
Cross-check Dashboard Usage.

Troubleshooting

Symptom	Reason	How to handle
The app still calls OpenAI using the ChatGPT account	Signed in through OAuth instead of using a custom API provider.	In Settings, switch to API / custom provider; ensure config.toml has model_provider = thapi.

Codex CLI · API CLI