Plaid Read-Only MCP Server

This is a local stdio MCP server that exposes read-only Plaid data retrieval tools. It does not expose Link token creation, token exchange, sandbox mutation, transfer, payment, processor, or item mutation endpoints.

Setup

npm install
npm run build

Create a .env file from env.example, or provide these variables through your MCP client:

PLAID_CLIENT_ID=...
PLAID_SECRET=...
PLAID_ENV=sandbox
PLAID_ACCESS_TOKEN=...
PLAID_VERSION=2020-09-14

PLAID_ACCESS_TOKEN is optional at process startup because each tool also accepts an access_token argument. If neither is supplied, access-token tools return a clear configuration error.

MCP Client Configuration

Use the built server with a stdio MCP client:

{
  "mcpServers": {
    "plaid": {
      "command": "node",
      "args": ["C:\\path\\to\\plaid-readonly-mcp\\dist\\index.js"],
      "env": {
        "PLAID_CLIENT_ID": "your-client-id",
        "PLAID_SECRET": "your-secret",
        "PLAID_ENV": "sandbox",
        "PLAID_ACCESS_TOKEN": "optional-default-access-token"
      }
    }
  }
}

Tools

• plaid_get_item
• plaid_get_accounts
• plaid_get_balances
• plaid_get_transactions
• plaid_sync_transactions
• plaid_get_identity
• plaid_get_auth
• plaid_get_liabilities
• plaid_get_investment_holdings
• plaid_get_investment_transactions
• plaid_get_institution
• plaid_list_institutions

All Plaid responses are returned as formatted JSON text.

Connect A Bank With Plaid Link

The MCP server itself is read-only. The Plaid Link helper is not part of the MCP server; it performs Plaid token exchange during setup and writes PLAID_ACCESS_TOKEN to .env. Do not expose the helper publicly except temporarily during onboarding.

To connect a bank and obtain the PLAID_ACCESS_TOKEN the MCP server will read from, run the separate local Link helper:

npm run link

Open the printed URL, click Connect bank, complete Plaid Link, and the helper will exchange the temporary public_token and save the resulting PLAID_ACCESS_TOKEN into .env.

By default, the helper requests only the transactions product:

PLAID_PRODUCTS=transactions

You can override products with comma-separated env vars:

PLAID_PRODUCTS=transactions
PLAID_OPTIONAL_PRODUCTS=identity,liabilities,investments
PLAID_COUNTRY_CODES=US

For production OAuth institutions, Plaid requires an HTTPS redirect URI that has been added to your Plaid Dashboard. If you use a tunnel, open the helper through the tunnel URL and set the matching callback:

PLAID_REDIRECT_URI=https://your-tunnel-or-domain.example/oauth-return

To configure the redirect URI in Plaid, go here:

Plaid Dashboard -> Developers -> API

Then look for:

Allowed redirect URIs

Click Configure, add the exact URI from PLAID_REDIRECT_URI, then save:

https://your-tunnel-or-domain.example/oauth-return

Path in the dashboard:

Team settings -> API -> Allowed redirect URIs -> Configure

Plaid docs confirm this location and requirement: OAuth troubleshooting and OAuth guide.

The helper uses a two-tab OAuth flow: the setup tab stays open, Plaid Link opens in a separate tab, and the /oauth-return callback notifies the setup tab to resume Link with Plaid's receivedRedirectUri.