Overview

This guide walks you through connecting OpenAI Codex to Matrix using OpenClaw. You'll learn how to configure authentication, set up the channel, and deploy your AI assistant.

OpenAI Codex Features

  • 128K context window
  • Image generation and understanding
  • Tool/function calling
  • Fine-tuning available

Matrix Capabilities

  • Direct messages
  • Group chats
  • Media support
  • Reactions
  • Thread support

Step 1: Configure OpenAI Codex

Standard API key authentication

  1. Create an account at platform.openai.com
  2. Navigate to API Keys section
  3. Generate a new API key
  4. Set OPENAI_API_KEY environment variable

Environment variable: OPENAI_API_KEY

Step 2: Configure Matrix

  1. Create a Matrix account on your preferred homeserver
  2. Generate an access token
  3. Configure matrix in openclaw.json
  4. Start the gateway
  5. Invite the bot to rooms

Step 3: Combined Configuration

Add both configurations to your openclaw.json:

{
  "agents": {
    "defaults": {
      "model": {
        "primary": "openai-codex/gpt-5.2"
      }
    }
  },
  "models": {
    "providers": {
      "openai-codex": {
  "models": {
    "providers": {
      "openai-codex": {
        "apiKey": "${OPENAI_API_KEY}
    }
  },
  "channels": {
    "matrix": {
      "homeserver": "https://matrix.org",
      "accessToken": "${MATRIX_ACCESS_TOKEN}",
      "userId": "@mybot:matrix.org"
    }
  }
}
}

Step 4: Start the Gateway

# Start the gateway
openclaw gateway start

# Check status
openclaw status

# View logs
openclaw logs --follow

Access Control

Matrix supports the following access control policies:

DM Policies

Policy Description
allowlist Only senders in allowFrom list are processed
pairing Unknown senders receive a pairing code; admin must approve
open All DMs are processed (requires allowFrom: ["*"])

Group Policies

Policy Description
allowlist Only groups in groupAllowFrom are processed
open All groups are processed

Deploy Options

Choose how to deploy your OpenAI Codex + Matrix setup:

Local Deployment

Run on your personal machine with local-only access

View Guide →

VPS Deployment

Always-on deployment on a Linux VPS

View Guide →

Cloud Deployment

Managed container deployment on Fly.io or similar

View Guide →

Docker Deployment

Containerized deployment with Docker

View Guide →

Frequently Asked Questions

How do I set up OpenAI Codex with Matrix?
Configure OpenAI Codex as your AI provider and enable Matrix as a channel in openclaw.json. The gateway routes Matrix messages to OpenAI Codex for processing automatically.
Is OpenAI Codex a good choice for Matrix bots?
OpenAI Codex works great with Matrix. Extensive ecosystem and tooling and Good performance across tasks make it well-suited for Privacy-focused teams and Open source communities.