Codex

Updated: Sep 17, 2026

Overview

Codex should use the Device Access Toolkit GitHub repository as a plugin marketplace. This keeps Codex on the same git-backed Device Access Toolkit guidance that is published for Claude Code and other tools, instead of relying on pasted prompt text.
Once loaded, Codex has Device Access Toolkit-specific context and can help you:
  • Set up your project and add Device Access Toolkit SDK dependencies
  • Implement camera streaming, display, session lifecycle, and permissions
  • Write tests with Mock Device Kit
  • Debug common integration issues
For the best results, combine the Codex plugin with the Device Access Toolkit MCP server. The plugin provides coding patterns from the GitHub repo; MCP provides current published docs through search_dat_docs.

Setup

Add the Device Access Toolkit repository for your platform as a Codex plugin marketplace, then add the platform plugin.
iOS:
codex plugin marketplace add facebook/meta-wearables-dat-ios
codex plugin add mwdat-ios@mwdat-ios-marketplace
Android:
codex plugin marketplace add facebook/meta-wearables-dat-android
codex plugin add mwdat-android@mwdat-android-marketplace
If you already have a checkout of the Device Access Toolkit GitHub repo, add it as a local marketplace from the repo root, then add the same plugin:
codex plugin marketplace add .
codex plugin add mwdat-ios@mwdat-ios-marketplace
Use mwdat-android@mwdat-android-marketplace for an Android checkout.

Live docs lookup

Installing the Device Access Toolkit plugin also registers the hosted Device Access Toolkit docs MCP server. No separate MCP configuration is required.
Start a fresh Codex session if the running session cannot discover search_dat_docs, then confirm that both the plugin and tool are available before editing code. When Codex calls search_dat_docs, ask it to request Markdown-formatted results if the MCP client supports output formats.
Example prompt:

Use the installed Device Access Toolkit Codex plugin for implementation guidance. Then call search_dat_docs for current iOS camera streaming guidance, with Markdown-formatted results if available. Inspect my project first, make the smallest safe change, and run the relevant local checks.

Usage

Start Codex in your project directory and ask Device Access Toolkit-specific questions directly:

How do I set up camera streaming in my Android app? Write a test for my session lifecycle using MockDeviceKit. Implement a Device Access Toolkit display session for iOS and explain the required permission flow.

Adding the API reference

The Device Access Toolkit plugin covers setup and integration guidance. If you need exact API signatures or full reference content, provide the llms.txt URL in your prompt:

Use https://wearables.developer.meta.com/llms.txt?full=true as reference and show the current StreamSession configuration options.
Or add it to your local project guidance so it loads automatically:

## API Reference Fetch https://wearables.developer.meta.com/llms.txt?full=true for the Wearables Device Access Toolkit API reference.
Codex can use the plugin, MCP docs search, and llms.txt together: plugin for project patterns, MCP for current guides, and llms.txt for exact API reference details.