Connect Claude or ChatGPT

Updated 26 September 2026 5 min read

Connect Fakts to Claude, Claude Code, ChatGPT or Codex and ask about your invoices in your own words. The assistant reads from Fakts and, if you allow it, drafts invoices and quotes, adds clients and records payments. An invoice is issued or sent only when you approve it, unless you give the assistant that permission.

The connector address

Every assistant uses the same address. Copy it here:

https://mcp.fakts.lv/mcp

It works with any MCP client that supports remote servers with OAuth sign-in. Both the free and the paid plan can connect. A short overview is on the AI assistants feature page.

Claude

A connector you add at claude.ai works in Claude on the web, on the desktop and on your phone.

  1. At claude.ai, open Settings › Connectors and choose Add custom connector.
  2. Name it Fakts and paste https://mcp.fakts.lv/mcp as the URL.
  3. Choose Connect. Claude opens Fakts, where you sign in and choose what it may do (see below).

Anthropic's guide: Get started with custom connectors using remote MCP.

Claude Code

Run this in a terminal:

claude mcp add --transport http fakts https://mcp.fakts.lv/mcp

Then, in Claude Code, type /mcp, choose fakts and sign in in your browser.

ChatGPT

ChatGPT connects to remote MCP servers in developer mode.

  1. Turn on developer mode: Settings › Security and login › Developer mode. In a workspace, an admin has to turn it on first.
  2. Add a new app for a remote MCP server. Name it Fakts and paste https://mcp.fakts.lv/mcp as the URL.
  3. Connect it. ChatGPT opens Fakts, where you sign in and choose what it may do.

OpenAI's guides: Developer mode and MCP apps in ChatGPT and Apps in ChatGPT.

Codex

In the Codex app, Fakts is added as an MCP server.

  1. Open Settings › Plugins › MCPs, choose Add, then Add MCP server.
  2. Name it Fakts, choose Streamable HTTP and paste https://mcp.fakts.lv/mcp as the URL. Leave the token and header fields empty, and save.
  3. Choose Authenticate. Codex opens Fakts, where you sign in and choose what it may do.
  4. Ask in work mode: in a plain chat Codex does not use MCP tools.

OpenAI's guide: Model Context Protocol in Codex.

Signing in and choosing what it may do

When you connect, the assistant sends you to Fakts. Sign in with Google or an email link, as you normally do. Then one screen asks which companies the assistant may reach, if you belong to more than one, and what it may do there:

PermissionWhat it coversTo start
ReadInvoices, quotes, clients, items, bills, the VAT threshold, the PVN return preview, Enterprise Register records and ECB ratesAlways on
Create and editDrafts of invoices and quotes, clients and paymentsYour choice
Issue and sendIssuing and sending invoices without asking you in FaktsOff

Approving an invoice

Without the send permission, the assistant does not issue or send an invoice on its own. When it wants to, it gives you a link. Open it, look at the invoice in Fakts, and approve or decline.

  • The link is valid for 24 hours.
  • Any change to the draft voids it, so what goes out is exactly what you approved.

A draft is a real invoice: creating one takes the next number in its series, because Latvian law requires sequential numbering. Ask for a draft when you mean to issue it.

Several companies

If the connection reaches more than one company, the assistant asks you which one to use.

What the assistant can do

  • Read invoices, including overdue and unpaid ones, and quotes.
  • Read clients, catalogue items and bills.
  • Check the VAT threshold and preview the PVN return.
  • Look up companies in the Enterprise Register and read ECB exchange rates.
  • With the create and edit permission: add a client filled in from the register, draft invoices and quotes, and record payments.
  • Issue and send invoices, with your approval, or without it if you allowed that.

Limits

Each connection can make up to 1200 requests to Fakts an hour on the free plan and up to 6000 on the paid plan. One question can take several requests, such as finding a client and then its invoices.

Narrowing access or disconnecting

In Fakts, open Settings › Connected apps. There you can narrow the companies and permissions of each app, or disconnect it.

Your data

What the assistant reads from Fakts goes to the AI provider you chose, such as Anthropic for Claude or OpenAI for ChatGPT, and they handle it under your agreement with them. The privacy policy has the details.