taxapp.nz

taxapp.nz MCP server

Ask your AI app about your Tax App records in plain words: income, expenses, rental properties and New Zealand tax. Where your organisation allows it, it can add and change records too.

Tax App is a New Zealand app for households, sole traders and rental-property owners. It keeps income, expenses, contacts, rental properties and bank reconciliation in one place and works out indicative tax from Inland Revenue's rates. This MCP server is a remote server hosted by Tax App; this repository describes it and holds no code.

• Server address: https://mcp.taxapp.nz/mcp (remote, Streamable HTTP)
• MCP Registry name: nz.taxapp/taxapp
• Full guide: https://taxapp.nz/guides/ai-assistants/

Sign-in required

Every request needs you to sign in to Tax App. Your AI app opens the Tax App sign-in page when you connect; there is no key or password to copy into it.

Before you connect

1. You need a Tax App account. Sign up free.
2. An owner of your organisation turns AI connectors on in Settings > AI connectors (or while connecting) and chooses Read only or Read, add and change records.
3. Add the server in your AI app and sign in to Tax App when asked.

Configure it

VS Code (GitHub Copilot)

Add it from the @mcp gallery, or put this in your mcp.json:

{
  "servers": {
    "taxapp": {
      "type": "http",
      "url": "https://mcp.taxapp.nz/mcp"
    }
  }
}

Start the server, choose Allow when VS Code asks to sign in, sign in to Tax App, and tick the organisations it may reach.

Other AI apps

App	How
Claude (web, desktop, mobile)	Settings > Connectors > Add custom connector, name taxapp, URL https://mcp.taxapp.nz/mcp
Claude Code	claude mcp add --transport http taxapp https://mcp.taxapp.nz/mcp
ChatGPT	Settings > Apps (developer mode on) > create, URL https://mcp.taxapp.nz/mcp, authentication OAuth
Grok (web, phone apps)	grok.com/connectors (or Connectors in the app) > New Connector > Custom, name taxapp, URL https://mcp.taxapp.nz/mcp
Cursor	Add "taxapp": { "url": "https://mcp.taxapp.nz/mcp" } under mcpServers in ~/.cursor/mcp.json

How to use it

Ask in plain words, for example:

• "What is my estimated tax for this year?"
• "Which expenses did I record for the rental in March?"
• "Which bank transactions still need sorting?"
• "Add a $120 plumber bill for 12 Smith Street."
• "Add Jane Brown as a tenant at 12 Smith Street from 1 May at $650 a week."
• "The rent at 12 Smith Street goes up to $680 a week from 1 June."
• "Change last week's commission payment to $1,250."

The figures come straight from your records. The answer is written by the AI, so check anything that matters in the app. When a detail is unclear, such as which contact, property or expense account you mean, the AI app shows you the closest matches and asks.

Tax years are New Zealand income years (1 April to 31 March), named by the year they end in. Money is in New Zealand dollars.

Tools

Area	Read	Add and change
Organisations	list_organisations
Choices	list_choices (income, expense and contact types, IRD return lines, in your own words)
Tax year	get_tax_year_overview, get_tax_summary, get_profit_and_loss
Income	get_income_history, list_income, get_income_record	create_income (commission, rent or tenant reimbursement), update_income
Expenses	list_expenses, get_expense_record, list_expense_accounts	create_expense, update_expense, create_expense_account, update_expense_account
Contacts	list_contacts, list_contact_types	create_contact, update_contact, set_contact_paye_salary, set_contact_acc_classifications, create_contact_type, update_contact_type
Rental properties	list_properties (with tenancies), get_rental_report	create_property, update_property, create_tenancy, update_tenancy
Savings	get_savings_plan	update_savings_plan
Scheduled reports	list_scheduled_report_types, list_scheduled_reports (owners)	create_scheduled_report, update_scheduled_report (owners), send_scheduled_report_now
Bank	get_bank_inbox, get_reconciliation_status

Every tool is annotated: the read tools are read-only, the tools that change what is already there are marked destructive, and sending a report is marked as reaching outside Tax App. Adding and changing are refused unless an owner chose Read, add and change records, and never go beyond your own role. The AI app sends only what you tell it, such as dates, amounts and who paid: Tax App works out GST, KiwiSaver, ACC levy, tax and every total itself, exactly as it does on its own forms. Adding is safe to repeat: the same details sent again return the record already made. A change sends only the fields that change.

What it cannot do

• Delete anything
• Reconcile bank statements or change a match
• Change organisation settings, members or connections to other services
• See anything your own role cannot, or an organisation you did not tick
• File a return with Inland Revenue

Keeping it safe

• It signs in as you and never sees your password.
• Every change it makes is in the organisation's audit trail, marked as made through the AI connector.
• Owners see every AI connector under Settings > AI connectors and can remove any of them; switching AI connectors off ends them all.
• Changing your password ends every AI connector you made.
• What you share goes to the company behind your AI app, under its own terms, and may be kept outside New Zealand. Your records in Tax App stay where they are, in New Zealand.
• Tax, ACC and KiwiSaver figures are indicative workings from IRD rates, not an IRD assessment.

For app developers

• Authentication: OAuth 2.1 with PKCE (S256). A request without a valid sign-in gets HTTP 401 with a WWW-Authenticate challenge.
• Authorization server: https://api.taxapp.nz (dynamic client registration and client ID metadata documents)
• Protected resource metadata: https://mcp.taxapp.nz/.well-known/oauth-protected-resource/mcp
• Scope: taxapp. No API key, header or environment variable to configure.

More

• Full guide
• Privacy policy
• Help: [email protected]