Connect the VS Code Codex extension to LLMEasy with a custom model

The VS Code Codex extension does not require a separate Base URL and API Key field inside VS Code. It reads your local Codex configuration, so configure the LLMEasy provider in Codex config.toml.

If you do not see Base URL or API Key fields in VS Code settings, that is expected. Configure model requests for the VS Code Codex extension through the local Codex configuration.

Prerequisites

VS Code is installed
The Codex - OpenAI’s coding agent extension is installed
You have a LLMEasy API Key (sign up and get one)
You have copied an available model ID from the GPT Key group in the model plaza

Do not put your API Key in project files, AGENTS.md, sample .env files, or public repositories. The configuration below should stay in your local Codex configuration directory.

Setup methods

Recommended: use the Setup dialog
Manual configuration

After you create an API Key, the console opens a Setup dialog. From that dialog, copy API Key and Base URL, then choose a Codex setup method.

Select Codex

Select Codex under Available tools.

Choose a setup method

You can choose:

One-click Bash Configuration: copy the command and run it in your local terminal. Use this for quick setup.
CC Switch Integration: import the provider into CC Switch. Use this when you manage multiple tools.
Manual Configuration: copy API Key and Base URL, then write them into config.toml.

Restart VS Code

After the configuration is written, restart VS Code or run Developer: Reload Window so the Codex extension reads the local configuration again.

Find config.toml

The Codex configuration file is usually located at:

System	Configuration file
macOS / Linux	`~/.codex/config.toml`
Windows	`C:\Users\YOUR_USER\.codex\config.toml`
Windows + WSL	`~/.codex/config.toml` inside WSL

If the file does not exist, create it.

Add the LLMEasy provider

Add the configuration below to config.toml. If the file already contains the same top-level fields, merge the configuration instead of writing duplicate model_provider entries.

model_provider = "custom"
model = "gpt-5.5"
review_model = "gpt-5.4"
model_reasoning_effort = "high"
model_context_window = 1000000
model_auto_compact_token_limit = 900000
windows_wsl_setup_acknowledged = true

[model_providers]
[model_providers.custom]
name = "LLM Easy"
base_url = "https://www.llmeasy.ru/v1"
wire_api = "responses"
requires_openai_auth = true
experimental_bearer_token = "YOUR_API_KEY"
request_max_retries = 4
stream_max_retries = 8
stream_idle_timeout_ms = 300000
supports_websockets = false

Replace YOUR_API_KEY with your LLMEasy API Key.

Confirm the key fields

Check these fields first:

Field	Value
`base_url`	`https://www.llmeasy.ru/v1`
`wire_api`	`responses`
`model`	A model ID copied from the GPT Key group
`experimental_bearer_token`	Your LLMEasy API Key

For the VS Code Codex extension, do not convert auth.json into an API Key-only structure. auth.json keeps the official Codex login state; the third-party API Key belongs in experimental_bearer_token.

Restart VS Code

After editing the file, close the current Codex session and restart VS Code.You can also run this from the command palette:

Developer: Reload Window

The VS Code Codex extension depends on Codex app-side capabilities such as the extension UI, session management, and VS Code integration. Keep the official login state while routing model requests through LLMEasy. In this configuration:

Setting	What it does
`requires_openai_auth = true`	Keeps the official Codex login state
`experimental_bearer_token = "YOUR_API_KEY"`	Uses your LLMEasy API Key for model requests
`base_url = "https://www.llmeasy.ru/v1"`	Sends model requests to LLMEasy’s OpenAI-compatible / Responses API endpoint

Verify the setup

After setup, open the Codex extension in VS Code and send a short test message. If you get a normal response, the configuration is active. If the request fails, check:

base_url is https://www.llmeasy.ru/v1
wire_api is responses
experimental_bearer_token has been replaced with your real API Key
model comes from the GPT Key group in the model plaza
Old OPENAI_API_KEY or OPENAI_BASE_URL environment variables are not overriding the configuration
VS Code has been restarted or reloaded

​Prerequisites

​Setup methods

​Why keep the official login state?

​Verify the setup

​Related docs

Prerequisites

Setup methods

Why keep the official login state?

Verify the setup

Related docs