Codex Assist for Home Assistant (Marketplace integration)

Installs: 135 sharing analytics
GitHub stars: 23
Connection: Uses the vendor's cloud
Upkeep: Updated in the last 6 months
Version: v0.4.10, October 24, 2026
Category: AI and voice, AI models
Kind: Marketplace integration
Needs: Needs the Marketplace (HACS on 2026.10 and older)
Domain: codex_assist
Source: github.com/itsreverence/ha-codex-assist
Issues: Report an issue

Independent directory, made by the developer of Vulpo. Not affiliated with Home Assistant or the Open Home Foundation.

Screenshots From the README of itsreverence/ha-codex-assist.

Example Assist chat in which Codex Assist reports that yard lights are on and turns them off

About

Codex Assist is an Assist conversation agent and AI Task provider that uses a ChatGPT or Codex subscription. It signs in through a device code approved in a browser, so no OpenAI API key is needed, and it relies on the vendor's cloud. As a conversation agent it streams replies and reads or controls only the entities exposed to Assist, through Home Assistant's own Assist LLM API. AI Task can produce plain text or structured data, read supported image attachments, and generate images. Options cover the chat model, response length, a system prompt, reasoning effort, and default image quality and size. Hosted web search is available but off by default. The project describes itself as experimental and unaffiliated with OpenAI or Home Assistant.

Automatic summary of the README and code of itsreverence/ha-codex-assist. Something wrong, or are you the maintainer and want your own text here? Get in touch

Supports

Uses the vendor's cloud Needs an internet connection and an account with the vendor.
From the Marketplace Installed through the Marketplace, formerly HACS.
Actively maintained Its author released or pushed a change in the last six months.

Setting it up

Install it from the Marketplace and restart Home Assistant, then add it under Settings, Devices and services.

Choose a chat model

Chat model

After setup

Chat modelThe model used for Assist conversations and AI Task requests.
Response lengthHow concise or detailed normal text and voice responses should be.
Enable hosted web searchAllow the model to search the web for current information. Search is off by default.
System promptStanding instructions applied to Assist conversations.
Reasoning effortHow much reasoning supported models should use before answering.
Image qualityDefault quality for images created through Home Assistant AI Task.
Image sizeDefault shape and resolution for generated images.

Texts from the code of itsreverence/ha-codex-assist.

Troubleshooting

DiagnosticsDownloads a diagnostics file to attach to a bug report.

From the README

Use OpenAI Codex / ChatGPT as a Home Assistant Assist conversation agent and AI Task provider.
Codex Assist signs in with Codex-style ChatGPT device-code auth. It keeps device control inside Home Assistant's normal exposed-entity safety model and does not require an OpenAI API key.

From the README of itsreverence/ha-codex-assist, MIT License. Shortened.