Connect Codex to LLMEasy with a custom model

Connecting Codex to LLMEasy requires a custom model provider and API Key. The base_url must be https://www.llmeasy.ru/v1, and the protocol is OpenAI Responses.

If you want to keep the official Codex App login state, plugins, or Remote Control while using a third-party API, use the login-preserving Codex setup.

Prerequisites

Node.js installed
LLMEasy API Key (register here)

Clear OpenAI-related environment variables before setup so they do not override the settings in config.toml.Clear these variables:

OPENAI_API_KEY
OPENAI_BASE_URL

Run on macOS / Linux:

unset OPENAI_API_KEY
unset OPENAI_BASE_URL

Run in Windows PowerShell:

Remove-Item Env:OPENAI_API_KEY -ErrorAction SilentlyContinue
Remove-Item Env:OPENAI_BASE_URL -ErrorAction SilentlyContinue
[Environment]::SetEnvironmentVariable("OPENAI_API_KEY", $null, "User")
[Environment]::SetEnvironmentVariable("OPENAI_BASE_URL", $null, "User")

Install Codex

npm install -g @openai/codex

Setup

Automatic setup
Configure via CC Switch
Manual setup

You can run the LLMEasy automatic setup script directly. It only writes the LLMEasy provider configuration and does not replace the installation prerequisites above. The script requires Node.js. If you do not pass an API Key or model explicitly, the script prompts for them when the tool supports interactive input.Follow the step for your operating system. You only need one of them.

If you use macOS / Linux

curl -fsSL https://www.llmeasy.ru/install-codex-provider.sh | bash

If you use Windows

iwr https://www.llmeasy.ru/install-codex-provider.ps1 -OutFile "$env:TEMP\install-codex-provider.ps1"; powershell -ExecutionPolicy Bypass -File "$env:TEMP\install-codex-provider.ps1"

Confirm the default models

The config below uses gpt-5.5 as the default model and gpt-5.4 as the review model. If you need to switch models, open the LLMEasy model plaza and copy a currently available model ID from the GPT Key group.

Confirm the config file locations

Manual setup requires the Codex config.toml file.

System	`config.toml`
macOS / Linux	`~/.codex/config.toml`
Windows	`C:\Users\YOUR_USER\.codex\config.toml`

Edit the Codex config file

Open config.toml. Create it if it does not exist.

This config only applies when you manually edit ~/.codex/config.toml. If you configure Codex through CC Switch, follow the CC Switch guide exactly. Do not copy this block to replace configuration managed by CC Switch.

Add the following config:

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 = false
request_max_retries = 4
stream_max_retries = 8
stream_idle_timeout_ms = 300000
supports_websockets = false

Restart Codex in the terminal

After changing config.toml, stop the current Codex process and start it again in a new terminal session.

Start Codex

codex

Config parameter reference

The official Codex config reference explains that model_provider points to a provider id under model_providers, custom providers are defined with [model_providers.<id>], and wire_api = "responses" is the supported provider protocol value.

Config	Meaning	Recommended value
`model_provider`	Selects the model provider Codex uses. The value must match `[model_providers.custom]`.	`"custom"`
`model`	The default main model Codex uses for everyday coding, editing, and agent tasks.	`"gpt-5.5"`
`review_model`	The model used by the `/review` command. If unset, Codex uses the current main model.	`"gpt-5.4"`
`model_reasoning_effort`	Controls reasoning strength for models that support the Responses API. Valid values include `minimal`, `low`, `medium`, `high`, and `xhigh`.	`"high"`
`model_context_window`	Tells Codex the active model context window size in tokens.	`1000000`
`model_auto_compact_token_limit`	Automatically compacts conversation history when it reaches this token threshold.	`900000`
`windows_wsl_setup_acknowledged`	A Windows / WSL onboarding acknowledgement flag, mainly used to avoid repeated setup prompts.	`true`
`[model_providers]`	Parent table for custom model provider configuration.	`[model_providers]`
`[model_providers.custom]`	Defines a custom provider with the id `custom`; `model_provider = "custom"` references this table.	`[model_providers.custom]`
`name`	Provider display name. It only affects presentation, not request behavior.	`"LLM Easy"`
`base_url`	API base URL. Codex sends model requests to this endpoint.	`"https://www.llmeasy.ru/v1"`
`wire_api`	Provider protocol. In Codex provider config, `responses` is the supported value and the default.	`"responses"`
`requires_openai_auth`	Whether to use official OpenAI authentication. This custom proxy provider disables OpenAI auth.	`false`
`request_max_retries`	Maximum retry count for ordinary failed HTTP requests. The official default is `4`.	`4`
`stream_max_retries`	Maximum retry count for interrupted SSE streams. The official default is `5`; proxy chains can use a higher value.	`8`
`stream_idle_timeout_ms`	Idle timeout for SSE streams in milliseconds. `300000` equals 5 minutes.	`300000`
`supports_websockets`	Whether this provider declares support for the Responses API WebSocket transport.	`false`

Note: The gpt-5.5 model page shows that it supports high reasoning effort and has a 1,050,000 token context window. Setting model_context_window = 1000000 is a reasonable conservative value, while model_auto_compact_token_limit = 900000 delays compaction and fits heavy long-running tasks.If you write the config through CC Switch, prefer the config generated by CC Switch. Only edit these values yourself for manual setup or troubleshooting.

Verify the setup

After startup, send a test message. A normal reply means the connection is working. If something fails, check:

base_url is https://www.llmeasy.ru/v1
wire_api is still responses
model is a model ID copied from the GPT Key group
model_provider matches the provider id in [model_providers.custom]
No old OPENAI_API_KEY or OPENAI_BASE_URL variables are interfering

​Prerequisites

​Install Codex

​Setup

​Config parameter reference

​Related FAQ

​Verify the setup

Prerequisites

Install Codex

Setup

Config parameter reference

Related FAQ

Verify the setup