SimpleFIN MCP

Connect your finances to your agents: a self-hosted MCP server for SimpleFIN, deployed at https://simplefin-mcp.vercel.app.

Use

1. Deploy your own copy with an OWNER_PASSWORD and a Neon Postgres database from the Vercel Marketplace (sets DATABASE_URL). The tables are created on first use.
2. Create a setup token in SimpleFin Bridge.
3. Paste it on /setup (unlocked with OWNER_PASSWORD). You get a connector URL, shown once.
4. Add that URL as a custom connector (MCP server) in Claude, ChatGPT, or any MCP client.

Tools (read-only): list_accounts, get_transactions, spending_summary, get_holdings, get_connection_status. Data is cached per connection for 4 hours (lib/data.ts) because SimpleFin Bridge allows ~24 requests/day and recommends at most 45 days per request.

How it works

• app/actions.ts claims the setup token and creates a connection (lib/connections.ts).
• Each connection is a row in the Postgres connections table: the SHA-256 of a random connection key, plus the SimpleFin access URL AES-256-GCM-encrypted under a key derived from it. The connection key exists only in the user's connector URL.
• app/mcp/route.ts looks up the key (Authorization: Bearer or ?key=), decrypts the access URL, and serves the tool.

Develop

CI=true pnpm install --frozen-lockfile
pnpm verify   # format, typecheck, test

Copy .env.example to .env.local for local runs. The schema lives in lib/db.ts.