How to connect an AI

Connect your own AI assistant to your books in CORE Books AI, so you can ask it about your numbers and, if you allow it, have it categorize transactions for you.

What an AI connection is

An AI connection lets your own AI, such as Claude, ChatGPT, Grok, Cursor or any other app that supports MCP connectors, read your books in CORE Books AI. If you allow it, it can also categorize transactions and save rules when you tell it to.

You sign in to CORE Books AI from inside your AI app and choose exactly which businesses it can see and what it may do. You can change that or disconnect at any time.

The address to paste

Every AI app asks for the same thing: the address of the connector. Copy this one.

Connector address

https://corebooksai.com/api/mcp

There is no key or password to paste. When your AI app connects, it opens a CORE Books AI sign-in page, and that is where you give permission.

Claude (claude.ai, the desktop app and the phone app)

In Claude, open Customize, then Connectors.
Choose Add, then Add custom connector.
Give it a name, such as CORE Books AI, and paste the connector address.
Choose Continue. Under Authentication choose Sign in now, and leave the OAuth client setting as it is.
Choose Add. Claude opens the CORE Books AI sign-in page; finish there (see "What happens when you connect" below).
In a chat, select the + button, then Connectors, and make sure the connector is switched on for that chat.

On a Claude Team or Enterprise plan, an owner adds the connector for the organization first under Organization settings, then Connectors. Each person then finds it under Customize, then Connectors, and chooses Connect. Claude says custom connectors work on its Free, Pro, Max, Team and Enterprise plans, and a Free account can add one.

A connector you add on claude.ai also works in the Claude desktop and phone apps. Menu names can differ by version.

Checked against: Claude Help Center: Get started with custom connectors using remote MCP · Claude docs: Remote MCP custom connectors

ChatGPT

In ChatGPT, open the page where you add apps, connectors or plugins. OpenAI currently calls it Plugins; on some accounts it is under Settings, then Apps and Connectors, and you may need to turn on Developer mode in the advanced settings first.
Choose the + button, then the option to add a custom MCP server.
Give it a name, such as CORE Books AI, a short description, and paste the connector address as its URL.
Choose OAuth for sign-in, accept the warning about custom connectors, and create it.
ChatGPT opens the CORE Books AI sign-in page; finish there (see "What happens when you connect" below).
Start a new chat and pick the connector, for example by typing @ and choosing it.

Adding your own MCP connector is only available on some ChatGPT plans, and OpenAI describes parts of it as a beta. On Business, Enterprise and Edu plans a workspace admin may need to turn on developer mode before you can add one. Check what your ChatGPT plan includes.

Menu names can differ by version.

Checked against: OpenAI Apps SDK: Connect from ChatGPT · OpenAI Help Center: Developer mode and MCP apps in ChatGPT

Cursor

Open (or create) the file mcp.json: ~/.cursor/mcp.json for every project, or .cursor/mcp.json inside one project.
Add the entry below. If the file already lists other servers, add this one next to them inside mcpServers.
Save the file. Cursor opens the CORE Books AI sign-in page the first time it connects; finish there.
Check that the server is switched on in Cursor where MCP servers are listed (Customize in current versions).

mcp.json

{
  "mcpServers": {
    "core-books-ai": {
      "url": "https://corebooksai.com/api/mcp"
    }
  }
}

Menu names can differ by version.

Checked against: Cursor docs: Model Context Protocol

Any other AI app

Any AI app that supports remote MCP servers with OAuth sign-in can connect. The steps are nearly always the same:

Find where the app adds a connector, integration, tool or MCP server.
Choose to add a remote (URL or HTTP) server and paste the connector address.
If it asks how to sign in, choose OAuth. There is no API key to enter.
Sign in to CORE Books AI on the page that opens and choose what the AI may do.

Some apps only work with servers on your own computer. Those cannot connect to CORE Books AI. Menu names can differ by version.

Apps that connect from the chat (Grok, Meta's Muse)

Some AI apps that work as agents, such as Grok and Meta's Muse, can add a connector right from a chat. Paste the connector address into the chat and ask it to connect, for example:

“Here is my connector for CORE Books AI: https://corebooksai.com/api/mcp. Connect it.”

The app sets up the connector and opens the CORE Books AI sign-in page; finish there (see "What happens when you connect" below). If your app does not connect this way, add the connector in its settings instead.

Claude does not add connectors from a chat. In Claude, add it in Customize, then Connectors, as above.

What happens when you connect

You sign in to CORE Books AI with your usual login.
You choose which businesses this AI can use. Only businesses on Co-Pilot or Command can be chosen.
The AI can always read your books. If you also want it to categorize for you, tick the one box on the page: "Let your AI categorize transactions and make rules for these businesses, instead of Cash." The page shows your AI's name. It is off unless you tick it. Left off, Cash keeps categorizing.
If you tick it, confirm it is you: enter your password, the code from your authenticator app, or a code we email you.
Choose Connect. You go back to your AI app, ready to ask.

With the box ticked, your AI categorizes every business you chose, in place of Cash or any other AI. If you are not the owner, accountant or a team member of a business, the page says you cannot change who categorizes it, and that stays as it is.

Connecting the same AI app again replaces the old connection once the new one has connected, and anything the old one categorized moves to the new one.

Suggest only, who categorizes each business and which AI does it are all in Settings, then Your assistant, then AI connections. You can change them there any time.

What each permission means

Read your books: Always on. The AI can see your reports, accounts, categories, rules and transactions for the businesses you chose. It cannot change anything with this alone.
Categorize transactions: The AI can file the transactions it is sure about and answer your review queue. Anything it is unsure about waits for your review.
Rules: With categorizing allowed, the AI can make, change, turn off and delete categorization rules, including renaming a vendor, but only when you ask it to. It checks with you before a rule changes past transactions. A Suggest only connection cannot save rules.
Classes: On Command, the AI can see each transaction's class. With categorizing allowed, it can give transactions a class or take one off, but only when you ask it to. A class changes no category and no money.
Suggest only: The AI suggests a category but files nothing. Every suggestion waits in your review queue for you to approve. Turn it on in Settings, under AI connections.

Some things the AI can never change, even if you ask:

Matched transfers and card payments between your accounts
Starting balances
Loan payments split into interest and principal
Deleted transactions

If a person already decided a transaction, the AI leaves it alone unless you tell it to change it.

Everything can be undone. Ask your AI to "undo the last categorization", "undo the last rule change" or "undo the last class change".

What your AI can do

Reports and transactions: Read the profit and loss, balance sheet and cash flow, look up transactions, and see what changed since you last talked.
Categorizing: Categorize transactions and answer your review queue, with undo.
Categories: Add custom revenue and expense categories, and sub-accounts on Command.
Rules: Make, change, turn off and delete categorization rules, with undo.
Classes: Give transactions a class or take one off (Command), with undo.
Projects: Start projects for your jobs, change or close them, and put transactions on them, so each job shows its own profit and loss.
Mileage: Log your business trips, change or delete one, and total your mileage deduction for any dates.
Earlier transactions to move: See the earlier transactions CORE Books categorized on its own that now have a better answer, and move them when you say yes, with undo.
Suspected duplicates: Go through transactions that look doubled: remove the extra one, keep both, or dismiss the pair, with undo.
Bills: Add vendors and bills, record a bill payment and void a bill (Command), with undo.
Journal entries: Record and void journal entries (Command), with undo.
Reconciling: Reconcile a bank or card account against a statement you give it, and attach the statement, with undo.
Moving your books in: Bring in a chart of accounts and a general ledger from another program, such as QuickBooks Online (Command), with undo.
Business memory: Remember what you tell it about your business, so Cash and the categorizer know it too, and forget a fact when you say so.
Tax settings: Change a business's entity type (and the date it took effect), the owner's S-corp salary, its tax form (Schedule C or E) and tax method (cash or accrual), and the owner's personal tax profile (filing status, state, W-2 and other income, withholding, dependents).

Reading needs nothing more. Changes need a connection that may categorize (not Suggest only). Apart from categorizing, undo and remembering what you tell it, your AI shows you the exact change and waits for your yes before it makes it.

Things to ask

“Show me my profit and loss for last quarter.”
“How much did I spend at Amazon this year?”
“What is in my review queue?”
“Categorize my review queue, and tell me what you were not sure about.”
“Make a rule that anything from Shell is categorized as Car and Truck Expenses.”
“Rename the vendor "SQ *BLUE BOTTLE" to Blue Bottle Coffee from now on.”
“What changed in my books since we last talked?”

Tips

Not sure how? Ask your AI: If you are not sure how to connect your AI app, ask it in a chat: "How do I connect an MCP connector?" Most AI apps can walk you through their own steps. Have the connector address ready to paste.
Start a new chat after we add features: AI apps remember the list of tools when a chat starts. When we add something new, start a new chat so your AI can see it.
See what your AI did: When your AI has categorized, held or changed transactions, or made rules, a "What your AI did" notice appears on your dashboard. On Activity, turn on the "Changed by your AI" filter to see exactly which transactions it touched.
Disconnect: Go to Settings, then Your assistant, then AI connections, and choose Disconnect. You can also remove the connector in your AI app. A connection also ends on its own after 90 days without use. Cash takes back categorizing for any business this AI was categorizing, unless another connected AI is set to categorize it.