settleup-kit

Unofficial Settle Up client, CLI and MCP server. Groups, members, expenses, transfers and debts — from your email and password, with nothing else to set up.

Not affiliated with Settle Up or Step Up Labs. Settle Up publishes a public API; this is a typed client for it.

Why this exists

Settle Up's API is a raw Firebase Realtime Database. That is a fine thing to publish, but it means every caller re-derives the same handful of facts: that the amount lives inside items[] rather than on the transaction, that member ids are per-group, that an empty description is refused as Permission denied, and that exchange rates divide rather than multiply.

This wraps that into named operations — "split 3200 yen between everyone" — and writes down what cost time to work out. See docs/traps.md.

Related MCP server: splitwise-mcp

Install

npm install -g @notsuhas/settleup-kit

From source:

git clone https://github.com/notsuhas/settleup-kit && cd settleup-kit
npm ci && npm run build && npm install -g .

Then:

export SETTLEUP_EMAIL="you@example.com"
export SETTLEUP_PASSWORD="…"

CLI

settleup login                    # once — signs in and caches the token
settleup groups                   # every group, with its members
settleup balances --group Lisbon   # who owes whom

Recording a shared cost. It defaults to you paying, split equally between every active member:

settleup add --group Lisbon --amount 3200 --purpose "Dinner" --currency EUR --category 🍽

added
2026-09-11        3200 EUR  🍽   Dinner        paid by Alice  for Alice, Bob
            id -Nq7xR2vK9mBpL4dTfWc

Override either side when it wasn't an even split:

settleup add --group Lisbon --amount 8000 --purpose "Hotel" --paid-by Bob
settleup add --group Lisbon --amount 1400 --purpose "Taxi"  --for "Alice,Bob"

Paying someone back, which settles a debt rather than adding a shared cost:

settleup pay --group Lisbon --amount 1000 --to Alice --from Bob

Editing and deleting take the id printed under each row:

settleup edit -Nq7xR2vK9mBpL4dTfWc --group Lisbon --amount 2900
settleup rm   -Nq7xR2vK9mBpL4dTfWc --group Lisbon

An edit changes only what you pass. The category, the split and any tip or tax lines survive an amount-only edit.

Groups and members:

settleup new-group --name "Lisbon 2026" --currency EUR --members "Alice,Bob"
settleup add-member --group "Lisbon 2026" --name Carol
settleup edit-group --group "Lisbon 2026" --name "Lisbon trip"
settleup rm-group   --group "Lisbon 2026"   # and every transaction in it

The first member is you — it is the one expenses default to being paid by.

--json on any command gives machine-readable output. --sandbox points at Settle Up's sandbox project instead of your real account.

MCP server

Seven tools: list_groups, group_balances, search_transactions, add_expense, add_transfer, edit_transaction, delete_transaction. Creating groups and members is opt-in behind SETTLEUP_MCP_ALLOW_STRUCTURE=1; delete_group needs SETTLEUP_MCP_ALLOW_DELETE=1 on top, because it takes every transaction in the group with it.

{
  "mcpServers": {
    "settleup": {
      "command": "npx",
      "args": ["-y", "-p", "@notsuhas/settleup-kit", "settleup-mcp"],
      "env": {
        "SETTLEUP_EMAIL": "you@example.com",
        "SETTLEUP_PASSWORD": "…"
      }
    }
  }
}

There is an HTTP transport too, for running it somewhere and pointing a client at it. It requires MCP_TOKEN and refuses to start without one.

Full notes: docs/mcp.md.

Library

import { createClient } from "@notsuhas/settleup-kit";

const su = createClient();

await su.groups();
await su.addExpense({
  group: "Lisbon",
  amount: 3200,
  purpose: "Dinner",
  currencyCode: "EUR",
});
await su.addTransfer({
  group: "Lisbon",
  amount: 1000,
  to: "Alice",
  from: "Bob",
});
await su.balances("Lisbon");

The CLI and the MCP server are both thin layers over this, so they cannot do anything the library can't.

Everything hangs off a group

Settle Up has no global notion of a person. Members, transactions and debts all belong to one group, and the same friend is a different member id in each — so every call names a group, and members are named within it.

Which member you are is read from the account, which is what lets "who paid" default to you.

Money

Amounts are always positive. Direction comes from the operation: add records money spent for the group, pay records one member paying another back.

A row carries its own currency, which need not be the group's. Settle Up converts on the server and reports debts in the group currency. Totals are summed as decimal strings rather than floats, because an expense splits into items and repeated float addition drifts.

The one thing to know before you start

A description is required. Settle Up's security rules reject a transaction whose purpose is empty, and the error is a bare Permission denied with HTTP 401 — which reads like an auth problem and sends you debugging the wrong thing.

This kit refuses an empty description locally, before the request goes out.

Environment

The token cache is written 0600 under ~/.config/settleup-kit/.

Docs

• docs/api.md — auth, paths, the transaction shape

• docs/traps.md — everything that cost time to work out

• docs/mcp.md — wiring the MCP server into a client

Licence

MIT. Use it against your own account.