Using custom MCPs with dots, via Codex CLI

I think it has become clear that OpenAI’s dots were released a bit early, likely due to the seeming success of Grok Bot. They’re slow, less capable than just using ChatGPT on a computer, and need a lot of guiding. But, it seems they are iterating quickly and I hope one day they will be as or more capable than how I currently interact with GPT.

One limitation I’ve had with dots has been that they cannot use custom MCPs. Dots can only use MPCs that are in OpenAI’s plugin marketplace and many of my MCPs aren’t there yet or perhaps never will be.

But I’ve found a workaround using a feature that OpenAI just released for dots. Dots can now use your devices. If one of those devices (say your Mac) has the custom MCPs configured on the Codex CLI, the dot can see them and use them.

Here is what the request looks like: dots → macOS → Codex CLI → custom MCPs.

Here is how you set it up (I’m hoping this is a temporary workaround):

• Install and sign in to Codex CLI on your Mac. Configure and authenticate your custom MCP servers there. Run codex mcp list to check the configuration, then test a simple read-only request.
• Connect your Mac to your dot using the new device access feature. In the ChatGPT desktop app, click your dot at the top, find This computer, and click connect.
• Ask your dot to run Codex CLI on that Mac, from the project directory where your MCP configuration works. Be specific about the connector and what you want it to do.

For example: “Use Codex CLI on my Mac to ask my WordPress MCP for my five most recent posts. Don’t change anything.” I tested this with the NerdPress Guided Agent Connector for my website. Codex CLI successfully read my WordPress posts through the connector.

The custom tools are running through Codex CLI. Connecting the Mac doesn’t add them directly to the dot, and each connector still needs working authentication and the right permissions.

Though they didn’t mention this specific workaround, you can find more tips about this new feature via pash on X.

As an aside: I used this workaround to draft this post. 🙂