Use Assindo in Codex (CLI, IDE Extension and ChatGPT Desktop App)

Codex can plan and write almost anything. What it cannot do on its own is make a real phone call and talk to a person. Assindo can. Assindo is an AI phone assistant: it calls businesses for you, works through phone menus, waits on hold, talks to whoever answers, and writes up what they said. Add Assindo to Codex as an MCP server and Codex can hand a call to Assindo, then check how it went.

The ChatGPT desktop app, the Codex CLI and the Codex IDE extension share the same MCP configuration, so a server you add in one is available in the others.

What You Need

Codex (CLI, IDE extension, or the ChatGPT desktop app).
An Assindo account. Free to create in the Assindo app (iOS, Android, or web at web.assindo.com). Calls use your Assindo plan's minutes.
The Assindo MCP server: https://mcp.assindo.com/mcp (Streamable HTTP, OAuth sign-in).

Option 1: The Codex CLI

Step 1: Add the server

codex mcp add assindo --url https://mcp.assindo.com/mcp

This writes the server to your config.toml:

Let Assindo answer your calls and make them for you.

Get Assindo

[mcp_servers.assindo]
url = "https://mcp.assindo.com/mcp"

Assindo supports dynamic client registration, so you do not need --oauth-client-id: Codex registers itself on first sign-in.

Step 2: Sign in

codex mcp login assindo

Your browser opens the Assindo sign-in page. Sign in with Google, Apple or email, the same login as the Assindo app. Codex catches the redirect on a local port, and the page says you will go back to "a desktop app on this device".

Option 2: The Desktop App or IDE Extension

In the desktop app, open Settings → MCP servers; in the IDE extension, open the gear menu, then MCP servers. Add a server, choose Streamable HTTP, and enter https://mcp.assindo.com/mcp. When Codex shows that the server needs sign-in, select Authenticate and sign in with your Assindo account.

Try It

"Use Assindo to call a bakery near me and ask if they can do a cake for 12 by Saturday."
A few minutes later: "Check the Assindo task: what did the bakery say?"
"Tomorrow at 9am, have Assindo call my internet provider and ask why my bill went up."

What Codex Can Ask Assindo to Do

Create a task (create_task). A phone call (book, ask, cancel, follow up), a post on X or LinkedIn, something at a set time, or research. The task description is all Assindo sees, so include the business and its number if you know it, exactly what to ask, and anything to avoid ("info only, do not book").
Check a task's result (get_task_result). The status, what Assindo found out, and the call summary. A call usually takes 2 to 5 minutes.
Send Assindo a message (send_chat_message). Ask what happened on a call, what is on your task list, or hand over a request in plain words.

Troubleshooting

The sign-in keeps coming back

Create your Assindo account in the Assindo app first. The connector signs you in to an existing account; it does not create one.
Use the same sign-in method as the app (Google, Apple or email).
Run codex mcp login assindo again: a fresh sign-in replaces the saved credentials.

The browser cannot reach Codex after sign-in

The redirect goes to a local listener on your machine, so sign in on the same computer Codex runs on. If something else needs a fixed port, set mcp_oauth_callback_port in config.toml (or mcp_servers.assindo.oauth.callback_port for this server only).

A call did not happen

Calls follow the same rules as the app: business hours only, no redialing someone who just declined, and your Assindo plan's minutes. If your plan has run out of minutes, the task result says so; check your plan in the Assindo app. Codex's own usage limits come from your ChatGPT plan.

FAQs

Does Codex dial the number itself?

No. It hands the job to Assindo as a task, and Assindo's own assistant places the call with the same rules as the app.

What about ChatGPT on the web?

ChatGPT on the web does not read your Codex configuration; it uses plugins instead. See Use Assindo in ChatGPT.

Does it cost extra?

No. Calls and tasks count against your normal Assindo plan.

Does Assindo work with other AI apps?

Yes: see the list of AI apps that work with Assindo. Assindo is also listed in the official MCP Registry as com.assindo/assindo.

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Give Codex a phone. Get Assindo and connect it.