Gnucash Mcp

gnucash-mcp

Free, open-source accounting software that works with the LLM.

Talk to your GnuCash books through Claude (or any AI assistant that supports MCP). Ask "how am I doing this month," dictate your transactions out loud, hand over the books for the AI to keep up while you focus on running your life or your business.

Your data stays on your machine. Your audit log stays on your machine. Nothing is uploaded anywhere — the AI reads and writes your local GnuCash file, and that's it.

Two real, populated sample books ship in this repo so you can try it before you commit anything. They're realistic — full years of activity, mixed currencies, customers, invoices, budgets, the works. Walk through one in five minutes; if it clicks, point the server at your own book and you're done.

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What does it look like?

This is what your AI assistant sees when it opens one of the sample books — a complete financial dashboard in a single call:

Book: samples/alex-chen-morales.gnucash
Currency: USD
Data range: 2025-01-01 to 2026-05-31
Last entry: 2026-05-31 (future-dated, 31 days ahead)
Warnings:
  ⚠ Past due invoice: Berlin Digital GmbH 58 days past 30-day default, EUR 4,200 (no term set)
  ⚠ Stale price: GBP last updated 150 days ago
Accounts: 108 total
Assets: 12 accounts, USD 602680.49
  Condo: USD 473250.00
  VTSAX: 230.7620 VTSAX @ 170.99 (USD 39457.99)
  Vehicle: USD 27845.00
  401k: USD 13404.62
  Checking Account: USD 12393.11
  ...
Liabilities: 4 accounts, USD 418457.79
  Credit cards (2): USD 38044.26
  Loans (2): USD 380413.53
  Top 3: Mortgage USD 372199.55, Chase Sapphire USD 22383.23, Business Amex USD 15661.03
Receivables: 3 accounts, USD 10246.46
  Accounts Receivable EUR: USD 4908.96
  Accounts Receivable: USD 3500.00
  Accounts Receivable CAD: USD 1837.50
Reconciliation:
  Checking Account: 174 splits unreconciled (4 months behind, oldest: 2025-12-30) ⚠
  7 accounts never reconciled ⚠
Net worth trajectory:
  12mo ago: USD 187,925
   6mo ago: USD 180,614
   3mo ago: USD 191,350
   1mo ago: USD 185,444
       now: USD 184,223
Monthly net (last 6 months):
  Apr 2026 (MTD): -9,056
  Mar 2026: +3,092
  Feb 2026: +5,202
  Jan 2026: +1,086
  Dec 2025: +4,853
  Nov 2025: -1,494
Runway: 121 days (USD 84,579 liquid / USD 694/day burn)
Budget (2026 Annual Budget): 41% used / 33% elapsed (+8% over pace)
Transactions: 2473
Scheduled: 13 recurring, none due in next 7 days
Business: 4 customers, 2 vendors, 1 employee

That's not a screenshot — that's the AI's actual orientation view. Net worth trajectory, runway, budget pacing, who owes you money, what's overdue, what hasn't been reconciled. One call, and your assistant has the full picture before you've even finished saying hello.

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Who is this for?

• Personal finance people who keep their books in GnuCash

and want to dictate transactions, ask their assistant where the money's going, get reconciliation help, plan budgets.

• Small business owners who run their books in GnuCash and

want to issue invoices, track receivables, see vendor spending, manage cash flow without leaving the conversation.

• People who care that their data stays local. No cloud

sync. No SaaS. Your .gnucash file is the system of record; this just gives your AI a way to read and write it the way GnuCash itself does.

You don't need to be a developer. You need:

• A computer (Mac, Windows, or Linux)
• GnuCash itself, or willingness to install it (free at

gnucash.org)

• An AI assistant that supports MCP (Claude Desktop is the

most common; Claude Code, Continue.dev, and others work too)

• 10 minutes to get the sample books running, then another 10

to point at your own

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Try it without risking anything

The repo ships two sample books — fully-populated synthetic ledgers you can talk to without touching your real data. Pick one, point the server at it, and start asking questions.

samples/alex-chen-morales.gnucash — Personal + freelance

A Seattle-based independent software contractor with a US LLC. USD-default. ~141 accounts, ~2,475 transactions across 2025–

1. Has a mortgage, a brokerage with VTSAX/VBTLX/AAPL/MSFT/ETH

holdings, a 401(k), four customers spanning USD/EUR/GBP/CAD with foreign-currency invoices, scheduled bills, a budget — pretty much everything the server can do, all in one book.

samples/lin-wei.gnucash — Cross-border small business

A Shenzhen-based small-business owner running a cross-border e-commerce operation. CNY-default. ~105 accounts, ~1,960 transactions. Chinese-named customers paying in CNY, USD/EUR customers paying in foreign currency with realized FX gain/loss on rate moves, domestic Chinese investments (茅台, 宁德时代, ETFs), an LPR-based mortgage, mixed payment rails (checking + Alipay + WeChat Pay).

Both books are fictional. See [samples/README.md](samples/README.md) for the full breakdown of what's in each.

---

Quick Start (5 minutes)

1. Install

git clone https://github.com/ninetails-io/gnucash-mcp.git
uv tool install --editable ./gnucash-mcp

That gives you a gnucash-mcp command on your PATH. --editable keeps it tracking the source, so a git pull shows up in the running server the next time it restarts. Skip --editable if you don't plan to update.

> If you don't have uv, install it with one line: > curl -LsSf https://astral.sh/uv/install.sh | sh

> For developers working against multiple worktrees, plain > uv sync inside the project directory still works — see > [For developers](#for-developers) below.

2. Make a working copy of a sample book

The server writes audit logs and auto-backups alongside the book file. You don't want either of those committed back to the repo, so copy the book somewhere outside the repo first:

mkdir -p ~/gnucash-mcp-scratch
cp gnucash-mcp/samples/alex-chen-morales.gnucash ~/gnucash-mcp-scratch/alex.gnucash

3. Tell Claude Desktop about the server

Find your Claude Desktop config:

• Mac: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json

Add this (replace the GNUCASH_BOOK_PATH value with your actual path):

{
  "mcpServers": {
    "gnucash": {
      "command": "gnucash-mcp",
      "args": ["--modules=all"],
      "env": {
        "GNUCASH_BOOK_PATH": "/Users/yourname/gnucash-mcp-scratch/alex.gnucash"
      }
    }
  }
}

--modules=all loads every tool (106 of them) so you can poke at anything. Once you know what you actually use, narrow it — see [choosing a module set](#choosing-a-module-set) below.

Quit Claude Desktop completely (not just close the window — quit) and reopen it. Look for the hammer 🔨 icon next to the text input. That means the server's connected.

4. Try it

Ask Claude:

• "Summarize the book."
• "What's my net worth been doing?"
• "Show me anyone who owes me money."
• "What did I spend on dining last month?"
• "Set a $500 monthly grocery budget."

The first response usually starts with the dashboard from above. Everything after that is conversational.

When you're ready to point at your own book, replace the GNUCASH_BOOK_PATH value with the path to your real .gnucash file (more on that next), restart Claude Desktop, and ask away.

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Connecting to your own book

One-time conversion: GnuCash file format

The server only reads the SQLite form of GnuCash files, not the older XML form. To convert:

1. Open your book in GnuCash itself
2. File → Save As
3. Change "Data Format" to SQLite3
4. Save with a new filename (e.g. mybook-sqlite.gnucash)
5. Keep the XML original as a backup.

You only do this once. From then on, GnuCash and the MCP server both work against the same SQLite file.

Set the path

Update GNUCASH_BOOK_PATH in your Claude Desktop config to point at your own SQLite-format book. Restart Claude Desktop.

> Use absolute paths, not ~ or relative paths. On > Mac/Linux: /Users/yourname/Documents/mybook.gnucash. On > Windows: C:\\Users\\yourname\\Documents\\mybook.gnucash > (note the doubled backslashes — that's a JSON requirement).

Other AI clients

This is an MCP server, so it works with any client that speaks MCP. Notes for non–Claude Desktop clients:

• Claude Code: claude mcp add-json gnucash '{"command":"gnucash-mcp","args":["--modules=all"],"env":{"GNUCASH_BOOK_PATH":"/path/to/your/book.gnucash"}}'

Add --scope user for all projects, --scope project for this one only.

• Anything else: set GNUCASH_BOOK_PATH and run

gnucash-mcp directly. Any client that can spawn a command and speak MCP over stdio will work.

---

Choosing a module set

--modules=all is the easy default — every tool, 106 of them. For day-to-day use you'll probably want less. Pick the role that matches how you'll talk to the server. Each role is a group that expands to the underlying tool modules; you can also pick the leaves individually for a finer cut.

| Role | What it gives you | Tools | |---|---|---| | core | Ledger primitives — accounts, transactions, balances, slots, audit log, backups, balance sheet, reconciliation. Always loaded. | 29 | | bookkeeper | Run reports, manage budgets, schedule recurring transactions. The personal-finance management cluster. (Reconciliation moved into core — any configuration that handles money needs it.) | 17 | | investor | Cost-basis tracking + price/commodity management. Tax-lot accounting needs prices to compute gains, so the bundle is the useful unit. | 12 | | freelancer | Customer invoicing + sales tax, plus billterms (payment terms), jobs (per-project P&L rollups), and credit notes (customer refunds). The full solo-consultant toolkit. | 31 | | business | Full small-business package — group alias that expands to freelancer (invoicing) plus business_complete (vendors, employees, bills, vouchers, vendor reports). | 48 |

Pick one or more, comma-separated:

"args": ["--modules=bookkeeper"]            // personal finance
"args": ["--modules=investor"]              // self-directed investor
"args": ["--modules=freelancer"]            // solo contractor
"args": ["--modules=business"]              // small business (= freelancer + business_complete)
"args": ["--modules=bookkeeper,investor,freelancer"]  // most things

core is force-added regardless; the explicit listing in the examples above is for clarity. The leaf modules behind each group (reconciliation, reporting, budgets, scheduling, tax_lots, portfolio, etc.) are individually selectable too — run gnucash-mcp --help for the full menu.

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What you can ask it to do

A non-exhaustive tour. Phrase any of these naturally — the assistant translates.

Recording activity

> "I spent \$47.50 at Safeway today on groceries, paid with my > Visa." > > Recorded: \$47.50 from Credit Card:Visa to > Expenses:Groceries on Apr 30, 2026. Description: "Safeway".

Setting up recurring bills

> "Set up my rent as a recurring bill. \$1,850 on the 1st of > every month from checking." > > Created scheduled transaction "Monthly Rent": \$1,850 > monthly, from Assets:Checking to Expenses:Rent. Next due: > May 1, 2026.

Investment tracking

> "I bought \$1,000 of VTSAX at \$170.99/share in my 401(k)." > > Recorded VTSAX purchase: 5.85 shares at \$170.99/share. Cost > basis: \$1,000.00. Lot created for capital-gains tracking > when you eventually sell.

Invoicing customers

> "Create a customer called Acme Corp and invoice them \$1,500 > for consulting." > > Created customer Acme Corp (id 000005) and invoice 000019: > 1× Consulting at \$1,500.00 = \$1,500.00. Open. Tell me when > you're ready to post it.

Foreign-currency invoicing

> "Invoice Berlin Digital €4,200 for Q1 retainer, due in 30 days." > > Created EUR invoice 000020 for Berlin Digital GmbH: > 1× Q1 Retainer at EUR 4,200 = EUR 4,200. Net 30. When they > pay, I'll book the realized exchange-rate gain/loss to your > FX account automatically.

Asking questions

> "How much did I spend with each vendor this year?" > > Office Depot: \$2,340 (4 bills, \$0 outstanding) > CloudHost Inc: \$1,200 (2 bills, \$600 outstanding) > Legal Associates: \$3,500 (1 bill, \$3,500 outstanding) > Total billed \$7,040 / paid \$2,940 / outstanding \$4,100.

Reconciliation

> "Help me reconcile checking against the April statement." > > [Walks you through it: pulls unreconciled splits, asks you > to confirm cleared transactions, computes the running > balance, marks the matched ones reconciled, leaves the > mismatches for you to investigate.]

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Privacy and safety

Your data does not leave your machine. This server is a local process that reads and writes a local file. The AI assistant you're talking to (Claude Desktop, etc.) sees the results of your tool calls — the same content you'd see on screen — but the file itself stays where it always was.

Every write is logged. A human-readable audit trail lives alongside your book file at .gnucash.mcp/audit/, one log file per day. You can read it at any time to see exactly what changed and when. Sample entry:

2026-04-30 14:32  POST INVOICE  id:000019
    total: 1500.00  date: 2026-04-30
    account: Assets:Accounts Receivable  txn:a1b2c3d4

Automatic backups. Before the very first write of each session, the server snapshots your book to .gnucash.mcp/backups/ — so if something goes wrong, you can roll back to a known-good state without relying on Time Machine or your own habit. Backups are verified with PRAGMA integrity_check before being declared valid. See [docs/RESTOREFROMBACKUP.md](docs/RESTOREFROMBACKUP.md) for the rollback procedure.

Reconciled splits are protected. The server refuses to delete or modify reconciled splits without an explicit override, so a careless prompt can't quietly invalidate your last bank reconciliation.

Voiding ≠ deleting. When you tell the AI to "void this transaction," it uses GnuCash's proper accounting void — preserving the transaction for the audit trail with values zeroed. Deletion is the destructive option; the AI will tell you which one it's doing.

> Disclaimer: This software is provided "as is" under the > [MIT License](LICENSE), without warranty of any kind. The > authors are not liable for any data loss, corruption, or > financial discrepancy arising from its use. You are solely > responsible for maintaining your own backups and verifying > the accuracy of your books.

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Limiting what the AI can see

Each tool's description lives in the AI's system prompt, which costs context on every message. Narrowing the toolset to what you actually use makes every conversation cheaper. See [choosing a module set](#choosing-a-module-set) above for the five role-based options (core, bookkeeper, investor, freelancer, business).

You can also set GNUCASH_MCP_MODULES=core,bookkeeper as an environment variable instead of --modules=... in the JSON args.

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What's in v1.3.1

This release fills in the business-feature complement promised since v1.2 and lands a deep correctness pass on the surfaces that were left rough — backed by an adversarial review of the whole codebase before the release branch opened.

Stage 3 business features:

• Taxtables — per-line-item sales-tax templates that flow

through invoice, bill, voucher, and credit-note posting.

• Jobs — multi-invoice project containers so a freelancer

can group all the invoices on one engagement under a single client deliverable.

• Credit notes — refund instruments with explicit

apply-to-invoice linkage, recognized as negative invoices through the same posting machinery.

• Employee expense vouchers — full lifecycle (create_voucher,

add_voucher_entry, post_invoice, pay_invoice) for reimbursement workflows.

**Role-aligned --modules partitio

…

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: ninetails-io
• Source: ninetails-io/gnucash-mcp
• License: MIT

Install and usage instructions live in the source repository linked above.