Your books, inside your AI app.

The Model Context Protocol is an open standard that lets AI apps use outside tools. Nefin's server at https://api-books.nefin.app/mcp gives an MCP client the same read and write tools as the in-app assistant, scoped to your account.

Claude, Claude Code, ChatGPT, Cursor, VS Code, Gemini CLI, Gemini and Gemini Enterprise, each with a step-by-step guide at nefin.app/integrations. Any other client that speaks MCP over HTTP with OAuth or a bearer token should work too; Account → AI connectors has ready-made setup for the editors.

26 tools, each working in one company at a time. Lists, searches, reports and balances only read. The others create drafts, record payments, run payroll or correct records, and every connection is read-only until you allow changes. Long jobs such as bank reconciliation and payroll come with a get_guide workflow the AI reads first, and every answer names the company it used and links to the record in Nefin.

Not unless you allow it. A connection is read-only until you tick "Allow changes" when you connect it. With changes allowed, writes such as creating an invoice or posting a journal are flagged, so clients like Claude ask you to approve them, and each one runs with your permissions and is recorded in the audit log.

Only companies where you are an active member, AI is switched on and the plan includes AI connectors. Ask it to list your Nefin companies to see exactly what it can reach; every tool call names the company it acts on.

Professional includes 20,000 tool calls a month per company and Business 100,000. At the limit, calls pause until the 1st of the next month. Starter companies show up as locked, with an upgrade link.

Answers Nefin returns are sent to the AI app you connected and handled under that provider's terms. Nefin keeps your data in its own region and logs every change a connector makes.