Vertex AI

Native MCP in the Gemini SDK.

Build a Gemini app on Vertex? The Gemini Python/JS SDK has a native MCP client — pass the BankBridge URL in your tools list.

Step 01

Register BankBridge as an MCP tool.

Python

from google import genai
from google.genai import types

client = genai.Client(vertexai=True, project="your-project", location="us-central1")

response = client.models.generate_content(
    model="gemini-2.0-flash",
    contents="How much did I spend on restaurants last month?",
    config=types.GenerateContentConfig(
        tools=[
            types.Tool(
                mcp=types.McpTool(
                    endpoint="https://bankbridge.money/api/mcp",
                    headers={"Authorization": "Bearer bbk_your_api_key_here"},
                )
            )
        ]
    ),
)
print(response.text)

The same shape works in the Agent Development Kit (ADK) — any ADK agent can attach MCP tools this way. Grab a key from your dashboard.

Step 02

Verify it works.

Run the script. You should see Gemini call list_transactions or get_spending_summary against BankBridge, then return a natural-language answer about March restaurants.

expected tool call

list_transactions({ category: "FOOD_AND_DRINK", start_date: "2026-03-01", end_date: "2026-03-31" })

Troubleshooting

Vertex returns 'Unknown tool' errors.

BankBridge's tool list wasn't fetched — usually an auth failure on the initial handshake.

Fix: Verify the Authorization header contains a real bbk_ key and that your Vertex project has outbound HTTPS allowed.

401 Unauthorized on every call.

The API key is missing, typo'd, or got revoked. Check the Authorization header starts with `Bearer ` (note the space) and ends in a key you still own.

Fix: Paste a fresh key from Settings.

403 Forbidden.

Your BankBridge subscription is inactive (canceled or past-due), or your account has no connected banks.

Fix: Visit Settings to confirm your subscription is active.

Tools return a NO_CONNECTIONS warning.

You haven't linked a bank yet.

Fix: Visit Connect a bank — the bank-connect flow opens automatically, ~30 seconds.

Problems? Email hello@bankbridge.money.