Connect EULER MCP to Gemini CLI — Step-by-Step Guide

Before you start

Make sure you have the following before following the steps below.

A Google account — used to sign in to Gemini CLI
Node.js installed — download free at nodejs.org
An EULER account with login access at eulerapp.com
A terminal — Terminal on Mac, Command Prompt or PowerShell on Windows

⚠

Gemini web interface limitation The Gemini web app at gemini.google.com does not currently support connecting custom MCP servers in the browser. Use Gemini CLI instead — it is free and runs on any operating system.

Step-by-step

Three steps to get EULER running in Gemini CLI.

1

Install Gemini CLI and sign in with Google

Open your terminal and install Gemini CLI:

npm install -g @google/gemini-cli

Then start the CLI:

gemini

The first time you run gemini, it asks whether you trust the current folder — select Yes, I trust the authors to continue.

Gemini CLI then asks how you want to sign in. Choose Sign in with Google.

Gemini CLI showing a sign-in prompt with 'Sign in with Google' highlighted — Select **Sign in with Google** to authenticate with your Google account

Gemini CLI opens a browser window for Google authentication. Complete the sign-in and return to the terminal — it displays Authentication succeeded when done.

Terminal showing 'Authentication succeeded' and a prompt to restart Gemini CLI — Once the browser authentication completes, the terminal confirms success. Press R to restart, or just close and re-run `gemini`.

Browser window showing 'Authentication successful' for the Google sign-in flow — The browser confirms your Google account is connected — close this window and return to the terminal

After restarting, Gemini CLI is ready and you are signed in with your Google account.

Gemini CLI interactive prompt showing signed in with Google account and ready for input — Gemini CLI is now ready. Your Google account is signed in — next, add EULER to the config file.

2

Add EULER to your settings file

First, quit Gemini CLI by typing /quit and pressing Enter.

Gemini CLI terminal showing /quit command entered and Gemini CLI exiting — Type `/quit` to exit Gemini CLI before editing the settings file

Gemini CLI reads MCP server configuration from a settings.json file. Create the folder if it does not exist, then open the file in a text editor:

mkdir -p ~/.gemini
nano ~/.gemini/settings.json

Operating system	Settings file location
Mac / Linux	`~/.gemini/settings.json`
Windows	`C:UsersYourName.geminisettings.json`

Terminal showing mkdir command and then nano editor opening settings.json with default content — Create the `.gemini` folder with `mkdir -p ~/.gemini`, then open the settings file in nano

Add the mcpServers block to the file. If the file already has content, merge the block into the existing JSON — do not replace the whole file:

{
  "mcpServers": {
    "euler": {
      "httpUrl": "https://mcp.eulerapp.com/mcp"
    }
  }
}

Save the file — in nano, press Ctrl+O then Enter to save, then Ctrl+X to exit.

Nano text editor showing settings.json with the mcpServers.euler.httpUrl block added, indicating Modified in the title bar — The `mcpServers` block added and saved — the nano title bar shows the file name after saving

ⓘ

Just the URL — no API key needed You only need the httpUrl field. Gemini CLI will prompt you to log in to your EULER account when you run the auth command in Step 3.

3

Authorize your EULER account

Start Gemini CLI again, then run /mcp to confirm the EULER server has been picked up:

gemini

/mcp

You will see euler listed with a status of Disconnected (OAuth not authenticated). This is expected — the next command starts the login flow.

Gemini CLI showing /mcp output with euler listed as Disconnected OAuth not authenticated — The euler server appears in the list but is not yet authorized — that is correct at this stage

Now run the authorization command:

/mcp auth euler

Gemini CLI opens a browser window pointing to the EULER login page:

Log in to your EULER account when prompted.
Select which accounts you want to grant the AI access to, then click Allow.
The browser shows "Authentication Successful" — close the window and return to the terminal.

✅

Authorization is saved You will not be asked to log in again. Run /mcp to confirm that euler shows as Connected, then start asking questions about your partner data.

💡

Pro tip — one-off questions Use the -p flag to ask a single question without opening the interactive shell:

gemini -p "Show me our top partners this quarter"

Troubleshooting

Common problems and how to fix them.

Problem	What to do
`command not found: gemini`	Node.js may not be installed. Download it from nodejs.org, then run the install command again. If Node.js is installed, try running `npx @google/gemini-cli` instead.
`/mcp` shows no servers listed	Check that `settings.json` is saved in the correct folder and that the JSON syntax is valid (no missing commas or brackets). Restart Gemini CLI after saving.
euler shows as Disconnected after auth	Run `/mcp auth euler` again. Make sure you clicked Allow on the EULER authorization page before closing the browser.
EULER returns empty results	Make sure your EULER account has data for the date range or query. Try a broader question to confirm the connection is working.
401 Unauthorized error	Your authorization session has expired. Remove the `euler` entry from `settings.json`, save, restart Gemini CLI, re-add the entry, and run `/mcp auth euler` again.

✉

Still need help? Contact EULER support at help@eulerapp.com — include any error messages you see and which operating system you are on.

Also available on Claude & ChatGPT

Prefer a chat interface? EULER connects the same way everywhere — one URL, one login, no API key.

See the Claude setup guide → See the ChatGPT setup guide →