Up Bank

A Cloudflare Workers-based MCP server for the Up Banking API. It can read your accounts and transactions, summarises spending, and can categorise and tag transactions.

Up's terms don't currently allow you to provide your personal access token to anyone else, so you will need to deploy your own instance of this system to your own Cloudflare.

Tools

Reads: ping, list_accounts, get_account, get_balances, list_categories, list_tags, get_transaction, list_transactions

Analysis: search_transactions, summarize_spending, cash_flow, find_recurring

Writes: categorize_transaction, add_transaction_tags, remove_transaction_tags

Setting It Up

Running this requires a Cloudflare account with Workers Paid: the free plan caps at 50 external subrequests and 10ms of CPU per invocation, and a year-long summary is dozens of Up requests and will involve processing before returning to your agent.

1. Create the KV namespace

npx wrangler kv namespace create OAUTH_KV

Paste the returned id over the placeholder in wrangler.jsonc.

2. Set the vars

Both live in wrangler.jsonc. PUBLIC_URL has to match the deployed Worker URL exactly, because it's what gets handed to the OAuth provider in preference to anything derived from the inbound Host header.

DEFAULT_TIMEZONE is the one line most people will need to change: Australia/Brisbane, /Sydney, /Melbourne, /Hobart, /Adelaide, /Darwin or /Perth. It decides where a month starts, so a wrong value here doesn't throw an error, it just quietly shifts your totals.

3. Set the secrets

npx wrangler secret put UP_API_TOKEN

npx wrangler secret put OWNER_PASSPHRASE

The Up token comes from https://api.up.com.au/getting_started. Generate the passphrase rather than picking one, for reasons in the design notes below:

openssl rand -base64 32

4. Deploy

npm run cf-typegen && npm run deploy

Add https://<your-host>/mcp to any MCP client. It'll ask for the passphrase the first time you connect.

5. Check It Works

BASE=https://<your-host> PASSPHRASE='...' npm run smoke

This walks the whole handshake, lists the tools, then runs real read-only queries against your account: balances, a 90-day category summary, cash flow and recurring detection. It calls no write tool and changes nothing. Worth running after the first deploy, and after any change to the auth path.

Local Development

cp .dev.vars.example .dev.vars

Fill it in, then:

npm run dev

npm run check

check runs the linter, the type-checker and 46 tests. The tests execute in workerd through @cloudflare/vitest-pool-workers, which matters more than it sounds like it does: the timezone logic depends on ICU, and that's the same ICU build production runs.

npm run smoke works against local dev too. If .dev.vars still has the placeholder token it reports Up's 401 as a pass and skips the Up-facing checks, so it's useful before you have a token as well as after.