How to trade with Gemini (Google)

How Gemini connects to tools

Google added custom MCP apps to the Gemini app in 2026 as part of Gemini Spark. You add a remote server by URL and Gemini signs in to it with OAuth; there is no field for a custom header, so the x-api-key header used by other clients can't be set in the app. OpenFinance supports OAuth sign-in, so the app path works without a key. Google currently limits custom apps to Gemini Spark (Google AI Ultra) on a personal Google Account, for users 18 or older in the United States, in English. Gemini CLI is separate: it reads servers from its own config file and does accept the key header.

Set up Gemini in under 60 seconds

1. Gemini app: on a computer, go to gemini.google.com and open Settings → Connected Apps.
2. Under Custom apps, click Add a custom app, name it OpenFinance and paste https://api.openfinance.tech/agent/mcp.
3. Click Next and sign in to OpenFinance when prompted.
4. Gemini CLI: run the command below instead (put your key in place of open_xxxxx).
5. In a chat, type @, choose OpenFinance, and ask for the BTC price to confirm it works.

gemini mcp add --scope user --transport http openfinance https://api.openfinance.tech/agent/mcp \
  -H "x-api-key: open_xxxxx"

Get your OpenFinance key at openfinance.tech (sidebar → External AI), then fund it with a debit card or crypto.

What Gemini can trade through OpenFinance

Gemini can trade crypto spot and leveraged perps on Hyperliquid, onchain stocks such as TSLA and NVDA, forex, Solana and Base memecoins, and Polymarket prediction markets, all with one OpenFinance account. Options are available through your own IBKR or Robinhood account connected in the OpenFinance app. The full market list is on the hub page.

Prompts to try in Gemini

• “@OpenFinance what's my balance, and what are BTC, ETH and SOL doing today?”
• “@OpenFinance go long BTC 5x with $50 on Hyperliquid and set a stop 4% below entry.”
• “@OpenFinance buy $25 of tokenized NVDA and $25 of TSLA.”
• “@OpenFinance show the top trending Solana memecoins and buy $10 of the one with the most volume.”
• “@OpenFinance what are the Polymarket odds on the next Fed decision? Bet $10 on the favourite.”
• “@OpenFinance show my open positions as a table.”

FAQ

Can Gemini trade crypto?
Yes, once OpenFinance is added as a custom app. Gemini calls OpenFinance's tools to quote, buy, sell and open perps, and asks you to confirm each action that moves money.

Where do I add an MCP server in Gemini?
On the web at gemini.google.com: Settings → Connected Apps → Custom apps → Add a custom app. Setup is web-only; after that the app is available in your Gemini account.

Who can use custom apps in Gemini?
Per Google: Gemini Spark (Google AI Ultra), a personal Google Account rather than a work or school account, 18 or older, in the United States, in English. If OpenFinance doesn't appear when you type @, check these first.

How does Gemini log in to OpenFinance?
With OAuth. Gemini can't send a custom x-api-key header, so it uses OpenFinance's OAuth sign-in instead of a key.

Is there a Gemini CLI setup?
Yes: gemini mcp add --transport http openfinance https://api.openfinance.tech/agent/mcp -H "x-api-key: open_xxxxx", or add an httpUrl entry under mcpServers in ~/.gemini/settings.json.

Can Gemini backtest?
Gemini can pull candles and reason over them. OpenFinance is for live execution; there's no paper mode, so ask it to simulate a trade first and start small.

How do I stop Gemini trading?
Remove OpenFinance under Settings → Connected Apps, or revoke its access in OpenFinance. For Gemini CLI, run gemini mcp remove openfinance.

Related

• Make any AI agent trading-compatible: every agent and market in one place
• Hyperliquid MCP server
• Polymarket MCP server
• Trade with Claude, Trade with Grok, Trade with Muse
• OpenFinance vs Alpaca vs CCXT: how OpenFinance compares with a broker API

Sources: https://support.google.com/gemini/answer/17209137, https://geminicli.com/docs/tools/mcp-server/

Trading involves risk, especially with leverage and memecoins. Start small.