Via MCP · connector ChatGPT, with your
accounting in reach.
Connect OneBooks to ChatGPT and it can search and fetch your invoices, customers and reports — with citations back to the record — ask for statements, and prepare documents you confirm. OAuth-secured, per business.
Search & fetch
answers cite the actual invoice or customer record
Human-confirmed writes
drafts only; nothing posts until you approve
No delete, ever
by design at the API level
Connected in two minutes.
Add the connector
In ChatGPT: Settings → Connectors → Add, with https://api.getonebooks.com/mcp. Developer mode exposes every tool; the standard connector uses search and fetch.
Sign in and approve
ChatGPT registers itself automatically over OAuth; you approve access for one business.
Ask
“Find Almara's open invoices”, “How much VAT 7.5% do I owe this quarter?”, “Draft an expense for the taxi receipt.”
Cited answers from your own records.
OneBooks implements ChatGPT's connector contract — search and fetch — so every answer can link to the record it came from.
- ✓ Search the books — invoices, purchases, customers, suppliers and items by number, name or reference.
- ✓ Fetch the record — the full document as text, with a link to open it in OneBooks.
- ✓ Reports — P&L, balance sheet, cash flow, aging and VAT 7.5% summaries (developer mode).
- ✓ Drafts you confirm — invoices, expenses, purchases and payments as proposals.
The same safety net as everywhere else.
One authorization surface, one set of rules, whichever AI is on the other end.
- ✓ OAuth per business — sign in, consent, revoke any time from Settings → Integrations.
- ✓ Minimized responses — connector results exclude internal identifiers and signing artefacts.
- ✓ Two-phase writes — proposals until a human confirms; no destructive tools exist.
- ✓ Rate-limited and metered — per-minute limits and a weekly cap per business.
ChatGPT connector — common questions
Does it work without developer mode?
Yes — OneBooks provides the search and fetch tools ChatGPT requires for standard connectors. Developer mode additionally exposes the full tool set, including reports and drafts.
Can ChatGPT change or delete my books?
No. It can read and propose; nothing posts without your explicit confirmation, and no delete, void or edit capability exists on the connector.
How is it authenticated?
OAuth 2.0 with PKCE. ChatGPT registers itself automatically; you approve access for one business, and tokens are bound to it.
What does it cost?
Connector usage draws from the same weekly AI-credit allowance as the built-in assistant — 200 credits per business per week.
Add OneBooks to ChatGPT.
Create your account, add the connector, and ask for last month's numbers.