Contha in Claude and ChatGPT
Ask about your money. Get your own numbers back.
Connect Contha to Claude or ChatGPT and ask in plain words: what you can spend, what you can pay yourself, what the IRS wants next and when. The answers come from your books, worked out the way the app works them out, across your personal and business money at once.
Works on the free plan: Claude and ChatGPT read your books at no charge, no card.
How much can I actually spend this month without touching the tax money?
Can I pay myself from the business this week?
File every Figma charge as business software from now on.
What to ask
The questions you would ask a bookkeeper
- “How am I doing this month?”
- “What bills are coming up before the 15th?”
- “What do I owe for Q4, and is it set aside?”
- “How much can I pay myself from the business?”
- “Find business expenses I filed as personal.”
- “Which budget lines am I over?”
- “How much did we spend eating out, and whose was it?”
- “What did I spend on software this year?”
- “I cancelled Netflix. Stop counting it.”
Claude also gets four ready-made requests in its menu: a money check-in, a quarterly tax check, find missed deductions, and a budget review. The tax and deduction ones need the Business plan, which keeps the business books.
Connect
About a minute, once
Want to try it before you sign up? Add https://demo.contha.com/api/mcp the same way: no sign-in, and it answers from the sample freelancer’s books. Add ?plan=personal to the address for the sample couple, or ?plan=shop for the Etsy shop. The sample only reads: asking it to file or budget is refused, because changes need your own books.
From Claude Code, in one line: claude mcp add --transport http contha-demo https://demo.contha.com/api/mcp
Claude
- In Claude, open Settings, then Connectors, and choose Add custom connector.
- Name it Contha and paste
https://app.contha.com/api/mcp - Choose Connect, sign in to Contha, and approve. Tick the box to let it file and add things only if you want that.
ChatGPT
- In ChatGPT’s settings, find Connectors (some plans call it Apps, and may ask you to turn on developer mode first).
- Add a custom connector with the address
https://app.contha.com/api/mcp - Sign in to Contha when it asks, and approve.
Using Claude Code, Cursor or a script? The developer page has a token setup for each, the full tool list and the REST API.
What it can and cannot do
It works as you, and never moves money
- Same numbers as the app. Free to use, the bills, the tax estimate: each is the figure the app shows, from the same calculation, not the assistant’s own arithmetic.
- Reads unless you say otherwise. On Personal and Business, when you approve, you choose whether it may also file transactions, add cash ones, set a budget or make a rule; on Free it reads only. It can never pay, transfer or touch a bank login.
- Your plan, your household. On Personal it sees your personal books; on Business, both books and the tax picture. A partner you invited as a viewer can connect too, read only.
- Nothing goes to Claude or ChatGPT until you ask. When you ask a question, it fetches what that question needs, and that conversation is under their terms. Separately, to file a charge your rules and our vendor list cannot, Contha asks a categorization service, TypeSafe, with the merchant, the bank’s description as the bank wrote it, the amount, the account’s name and type, and your category names. It does not send your account numbers, balances, name or email; the privacy policy says more.
- Off in one click. The connection shows in Contha’s Settings with when it was last used; revoke it and the next request is refused.
Getting started