Connect your AI
Your accounts,
in your AI assistant
Mighty has a built-in MCP server, so Claude, ChatGPT and other AI assistants can read your live numbers and draft your bookkeeping. Everything the AI drafts waits for your approval in Mighty, and your dedicated accountant still prepares and files the submissions to HMRC.
- Works with Claude, ChatGPT and other AI assistants
- Drafts for your approval, not changes behind your back
- Included in your plan
01How it works
Connected in a couple of minutes
- 1
Create a key.
In Mighty, go to Company settings and create an API key. It covers your organisation only, and you can revoke it at any time.
- 2
Connect your assistant.
Add Mighty as a connector in Claude, sign in from ChatGPT or Gemini, or point any MCP client at our server. The documentation has copy-paste setup for each.
- 3
Just ask.
What did I make last quarter?
,Which invoices are unpaid?
,Draft next month's invoice for Harbour Hardware.
Answers come from your live data; drafts land in Mighty for you to approve.
A strong month. September came in £2,140 ahead of August:
Two invoices from September are still unpaid, totalling £3,600.
02What your AI can do
Read everything, draft carefully
ReadsYour live numbers
Your assistant can see what you can see:
- Your dashboard, profit and loss, balance sheet and trial balance
- Sales invoices, paid and unpaid
- Bank accounts and transactions waiting to be categorised
- Receipts and documents in your Post Box
- Mileage claims and HMRC-rate distance lookups
DraftsWork for you to approve
And it can prepare work for you to approve:
- Draft a sales invoice, ready to check and send
- Suggest categories for bank transactions, saved as drafts you approve
- Turn a Post Box receipt into an expense for you to finalise
- Attach a receipt to the right bank transaction
- Log a mileage claim at HMRC's rates
03The human stays in the loop
AI drafts. You approve. Your accountant prepares.
This is deliberate, and it's policy, not a limitation. Your assistant can't approve a categorisation, raise money out of your books or send anything to HMRC. Its work arrives as drafts you approve in Mighty, every record it creates is labelled as AI-created so you and the Mighty team can always see what came from where, and your dedicated accountant still prepares and reviews your accounts and returns exactly as before.
Three layers between a chatbot's suggestion and your filed accounts.
- 1
AI drafts
Invoices, categorisations and expenses arrive as drafts, labelled AI-created.
- 2
You approve
Nothing counts in your books until you've checked it in Mighty.
- 3
Your accountant prepares
Your accounts and returns are prepared, reviewed and filed by a human.
04For developers
An API underneath, if you'd rather build
The same capabilities are available as a REST API: invoices, accounting periods, trial balance, profit and loss and balance sheet, with clean JSON and sensible paging. The documentation covers authentication, endpoints and limits.
- invoices
- accounting periods
- trial balance
- profit and loss
- balance sheet
Included in your plan
The MCP server and API come with every Mighty plan. No extra charge, no per-request fees.
per month
What is MCP?
The Model Context Protocol, an open standard that lets AI assistants like Claude and ChatGPT securely use tools and data from other products. Mighty runs an MCP server, so your assistant can work with your accounts.
Which AI tools work with Mighty?
Claude (web, desktop and Claude Code), ChatGPT, Gemini, and developer tools like Cursor and VS Code. Anything that speaks MCP can connect.
Can the AI change my books?
It drafts. Bank categorisations it suggests are always drafts for you to approve, invoices it creates arrive as drafts unless you explicitly tell it to raise one, and expenses from receipts wait for you to finalise. Mileage claims are the one direct entry: they post at HMRC's set rates, and you can remove one in Mighty.
Can it file anything with HMRC?
No. Your dedicated accountant prepares and files your returns and accounts, same as always.
How do I know what the AI did?
Every record created through a connected assistant is labelled as AI-created, so there's always a clear trail of what came from where.
Is my data safe?
Your API key reaches your organisation's Mighty data only, nothing else, and never your bank login. Treat the key like a password, and revoke it in Company settings at any time; revoking takes effect immediately.
Can my team connect too?
Yes, team members can use the connection on team plans.
Does it cost extra?
No, it's included in every plan.
What can I actually ask?
Anything your Mighty data can answer: how the quarter went, who hasn't paid, what's sitting unreconciled, what's in your Post Box, and "draft the usual invoice for..." requests.
I'm a developer. Is there a plain API?
Yes, a REST API with the same organisation-scoped keys. The documentation has endpoints, auth and limits.
Get in touch
Talk it through with an accountant
Book a free call and we'll show you how Mighty works, answer any questions you have and help you decide whether it's the right fit. Setting up an AI connection? Our technical team is happy to help.
"We'll be happy to discuss your business, answer any questions you have and discuss whether Mighty is a good fit for you."
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