Gemini Phone Calls: Add OsmO as a Custom App

Short answer: Gemini's own Call for me works only on US Pixel 10 and 11 phones. Gemini on the web can add a custom app by MCP address, but only for US personal accounts, set up on the web. If that is you, OsmO lets Gemini call businesses for you. Developers can also add OsmO to Gemini CLI or Antigravity CLI.

Custom apps: US, 18+, personal account, added on the web.

Gemini CLI: gemini mcp add --transport http osmo https://api.getosmo.app/mcp.

Outside the US, use OsmO in Claude, Grok or ChatGPT if your number is from Canada, the UK or Australia.

How it works

Sign in with your mobile numberYou get 50 free credits. Nothing to pay.
Add OsmO to GeminiChatGPT, Claude, Grok and other apps that take connectors.
Ask it to callOsmO calls, talks, and tells you what was said.

The full guide

Before you start

A US personal Google account, 18 or over, for custom apps; or Gemini CLI / Antigravity CLI.
A mobile number from the US, Canada, the UK or Australia (India also works) to receive a sign-in code.
Nothing to pay: you start with 50 free credits.

Connect OsmO to Gemini

On gemini.google.com, open Settings → Connected Apps and choose Add a custom app.
Paste https://api.getosmo.app/mcp. OsmO supports dynamic registration, so leave the credentials under "Show more" empty.
Sign in on OsmO's page with your mobile number and the texted code, then approve.
Ask Gemini for a call. Custom apps added on the web also work in the Gemini mobile app.

Who can add a custom app

Google lists the conditions: 18 or over, in the US, a personal Google account (not work or school), Keep Activity on and English. Outside those, if your mobile number is from the US, Canada, the UK, Australia or India, use OsmO in Claude, Grok or ChatGPT instead.

Gemini CLI and Antigravity CLI

Run gemini mcp add --transport http osmo https://api.getosmo.app/mcp, then /mcp auth osmo. Google moved free and Google One users from Gemini CLI to Antigravity CLI in June 2026; there, add OsmO as serverUrl in mcp_config.json and sign in when prompted.

Make a first test call

Make your first call a low-stakes one, such as asking a shop for its opening hours. You will see how your AI app confirms the call, how long a call takes and what the answer looks like, before you send it on anything that matters.

If something goes wrong

Common messages and what they mean
What you see	What it means	What to do
"You've used your free OsmO credits"	Not enough credits left for this request (each call needs 3)	Ask for fewer calls at once, or keep calling from the OsmO app: getosmo.app/app
"OsmO can call listed businesses and toll-free numbers"	The number is not a listed business, a toll-free line or one of your saved contacts	Give the business name instead. To call your contacts from your AI app, use the OsmO app, which syncs them
The sign-in page will not take your number	Sign-in accepts US, Canadian, UK, Australian and Indian mobile numbers	Use a mobile number from one of those countries
"Scheduling calls for later is available in the OsmO app"	Calls booked for a later time need the app	Ask for the call now, or schedule it in the OsmO app
A call is refused for the same number	OsmO places at most 5 calls to one number in any 24 hours	Try again once 24 hours have passed since the earliest of those calls

Turn it off

To disconnect, remove OsmO from your AI app's connector settings. Some apps do not tell OsmO when you do that. If you use the OsmO app, also open the Sharing card, then Connect AI apps, and tap Disconnect. If you only use OsmO from AI apps, email [email protected] with the mobile number you signed in with and we will end the access.

Questions people ask

Can Gemini call without asking me?

OsmO asks your AI app to read you who it will call and why, and to wait for your yes before it dials. Some apps also ask permission before using a connector at all.

Sources

Checked November 13, 2026. Vendors change their products often; follow the links for the current version.

How to make phone calls from Gemini: adding OsmO