Codex CLI

Configure Codex CLI to use Essevin's OpenAI Responses compatible API.

Codex CLI is OpenAI's coding agent. One-click setup is recommended; manual setup changes one configuration file.

Select a plan key

Sign in to the console, open Key Management, and find an OpenAI / Codex plan key.

Generate the setup command

Select One-click integration, then choose Codex CLI and your operating system.

Run and verify

Run the command in a terminal. When it completes, reopen the terminal and run codex.

For a graphical setup, follow the CC Switch guide, select Import CCS beside the key, and choose Codex CLI.

Manual setup: edit config.toml

SystemConfiguration file
macOS / Linux~/.codex/config.toml
WindowsC:\Users\your-name.codex\config.toml

Create the file if it does not exist, then add:

model_provider = "essevin"
model = "gpt-5.5"

[model_providers.essevin]
name = "Essevin"
base_url = "https://api.essevin.com/v1"
wire_api = "responses"
requires_openai_auth = true

Set the key and start Codex:

export OPENAI_API_KEY=sk-your-key
codex

Use a Codex plan key from a Codex Plus or Codex Pro group. See Troubleshooting when setup fails.

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