What it does
The VAT4U MCP links your VAT4U account to Claude, Anthropic's AI application. Once it is connected, you can ask Claude about your VAT4U data in plain language and get answers from your live account:
find and explain expenses, and why one is incomplete or not refundable
check what you could claim, per company and country
follow a VAT refund claim from creation to the tax administration's decision and any appeal
see your open tasks, notifications and imports
get secure download links for your documents
If you allow it, Claude can also make changes for you. For example, it can add invoices, request a claim or update company details. Each kind of change is a separate choice you make when you connect, and Claude asks you before every single change.
Claude sees exactly what you see in VAT4U, and nothing more. It works with your own permissions and your own company access. It cannot see another customer's data, or a company you do not have access to, however it is asked.
What it does not do: Claude never creates a VAT claim by itself.
Before you begin: what you need
A Claude account that can add custom connectors. Connectors work in Claude on the web (claude.ai), in the Claude desktop app and in Claude Code. If your organisation uses a Claude Team or Enterprise plan, an owner of your Claude organisation may need to add the connector for everyone first (see Step 1).
The Use AI Assistant permission on your VAT4U user. This permission is off by default. To have it turned on, contact VAT4U support or your account manager. The same permission also gives you the AI assistant inside VAT4U.
Your usual VAT4U sign-in. You sign in on VAT4U's own page, so your one-time code or email verification works as normal.
Step 1: Add the VAT4U connector in Claude
Claude on the web or the desktop app
Open Settings → Connectors.
Click Add custom connector.
Enter the name VAT4U, then click Add.
Click Connect next to VAT4U.
Connectors you add on claude.ai also appear in the Claude desktop app when you are signed in to the same account.
Claude Team or Enterprise
An owner of your Claude organisation adds VAT4U once, in the organisation's connector settings, using the same name and address. Each person then opens Settings → Connectors and clicks Connect to sign in with their own VAT4U account. Every person connects separately, and Claude only ever acts as the person who connected.
Step 2: Sign in and choose what Claude may do
When you click Connect, a browser window opens on VAT4U's sign-in page.
Sign in as you normally do, including your one-time code or email verification if your account uses one.
The Authorize access to VAT4U screen shows which account you are signed in as and what Claude is asking for.
Tick the changes you want to allow (see the table below), then click Authorize. Click Cancel to stop without connecting.
The "Authorize access to VAT4U" screen with the read access line and the list of opt-in boxes
Claude can always read your expenses, claims and companies. Every kind of change is a separate box, and no box includes any other. Leave every box unticked to keep Claude read-only.
Box on the screen | What it allows |
Request VAT claims | Prepare a claim for you to approve. Claude never creates a claim itself: it sends you an approval link, you check the claim in VAT4U and approve it there, and it is created as a draft for you to verify. |
Change expenses | Create and delete expenses, upload expense documents, add invoices and receipts, and have Smart AI fill in their details (this uses Smart AI transactions). |
Record and answer tax administration queries | Create, update and delete queries on your claims and attach documents to them. |
Change company settings | Create and delete companies, and change their name, address and contacts, VAT, invoicing and solution details, bank accounts, representatives, documents and tax certificates. |
Manage webhooks and your profile picture | Create and delete webhooks that send VAT4U events to other systems, and change your own profile picture. |
Once you click Authorize, you are returned to Claude and the connector shows as connected.
You can change your choices at any time. Disconnect VAT4U in Claude's connector settings and connect again, ticking a different set of boxes.
Step 3: Start asking
Open a new conversation in Claude and ask in your own words. You do not need to know any special commands. Some examples:
Expenses
"Which expenses for ACME GmbH are still incomplete, and why?"
"How many expenses from Germany did we have last quarter, and what is the total VAT?"
"Break down this year's expenses by country."
"Why was expense 48213 excluded?"
Claims
"What could we claim from France for last year?"
"Is there anything risky about a German claim for Q1? Look for duplicates, missing VAT numbers and unusual VAT rates."
"What did the tax administration decide on our Spanish claim, and was there an appeal?"
"Show me the history and messages on our latest Italian claim."
Reports and workspace
"How much VAT did we recover in 2025, and how does it compare with 2024?"
"Show me my open tasks and latest notifications."
"Did yesterday's import finish?"
Documents
"Give me a download link for the commercial register extracts of all my companies."
Claude answers from your live VAT4U data. Long lists come back 50 items at a time, and Claude can fetch the next 50 when you ask. For totals, Claude counts on VAT4U's side rather than reading every item, so totals are quick even for large accounts.
Adding invoices and receipts
Needs the Change expenses box.
Ask Claude in your own words, for example "Import these expenses to company ACME". You may also drop the files into the chat.
Files cannot travel from the chat into VAT4U. So instead of uploading them itself, Claude gives you a link to a VAT4U upload page:
Claude finds the company. It searches your own companies for the name you gave:
an exact name, or one that only differs in legal form ("ACME" for "ACME GmbH"), is used directly
a close match is confirmed with you first ("Did you mean ACME Trading SARL?")
several matches are listed with their countries, and Claude asks which one you mean
if nothing matches, Claude asks you to check the name
Claude gives you an upload link. Click it to open the Add your invoices to company page in VAT4U. The link works once, only for you, for 30 minutes.
Add the files. Choose or drag in PDF, JPG, PNG or TIFF files, up to 20 at a time, or one zip file for more. Then click Add these invoices. Each document becomes an expense in that company. If you picked a wrong file, the link stays usable so you can try again.
The page confirms. It shows Your invoices are on their way, and lists any files that were not added because they were not a PDF, JPG, PNG or TIFF document. You can close the page. The import carries on in VAT4U and usually finishes within a few minutes.
Ask Claude how it is going. Claude checks the import and only tells you the expenses are in once the import has finished.
Filling in the details (only if you agree). The new expenses hold the document, but not yet the invoice number, date, amounts or vendor. Claude tells you how many expenses Smart AI would fill in and how many Smart AI transactions that would use, and asks before it starts. For example: "Your 12 invoices are in. Shall I have Smart AI fill in the details? It uses 12 of your 340 Smart AI transactions."
If you say yes, Smart AI reads each document and fills in the invoice number, date, net, VAT and gross amounts, vendor and address, VAT number, currency, country and category. VAT4U then runs its usual checks. It costs one Smart AI transaction per expense, and an expense that has already been processed is never charged twice. A large import can take several minutes to fill in, and Claude can tell you how far it has got.
If you say no, the expenses stay as they are, and you can fill them in later in VAT4U.
Requesting a VAT claim
Needs the Request VAT claims box.
Claude never creates a claim by itself. A person always approves it in VAT4U.
Ask for the claim, for example "Prepare a French claim for ACME for 2025".
Claude checks it first. It runs the same checks as VAT4U's claim wizard and shows you the summary, any warnings and any risk findings. If something would stop the claim, Claude lists every problem at once so you can fix them together. Typical examples are missing claimant details, a bank account or representative that is not set up for claims, a period that is too short, or less than 50 EUR of VAT.
Claude sends you an approval link. It works once, only for you, for 15 minutes.
Check the claim in VAT4U. The Approve a VAT claim requested through the AI connector page shows the claimant, country of refund, period, VAT flow, number of expenses, totals and refund account. These figures come straight from VAT4U at that moment, not from anything Claude said.
Tick the declaration yourself for 8th and 13th directive claims. Claude can never tick it for you. If you forget, the link stays usable.
Click Approve and create draft to create the claim as a draft, or Decline to cancel the request. Either way, the link cannot be used again.
Verify the draft in VAT4U before you file it, exactly as with a claim you created yourself.
After approval, VAT4U prepares the claim attachment automatically from documents already in VAT4U: the required invoice copies, additional claim documents, the saved power of attorney and the bank information file. Anything that needs your attention appears in the claim's messages within a few minutes.
More than one bank account and no default? Claude asks you which account the refund should go to rather than choosing one.
Downloading documents
Claude never receives your files. When you ask for a document, Claude gives you a download link. The link opens only:
within 5 minutes of being created
once
in a browser where you are signed in to VAT4U as yourself
while you still have access to that document
A link that has been forwarded or leaked is useless to anyone else. If it has expired, ask Claude for a new one.
Your data and privacy
Claude works with your own VAT4U permissions and company access.
Your password stays with VAT4U. You sign in on VAT4U's own page. Claude only receives access for the choices you made, and VAT4U can withdraw it at any time.
Files stay in VAT4U. Documents only leave through single-use download links that work for you alone.
Changes are recorded. Every change attempted through the connector is logged in VAT4U with the time, the action and whether it succeeded.
The connector does not read your Claude conversations, memory or files.
Claude asks before every change
Reading is automatic. Every change — creating, updating or deleting anything — needs two things:
the matching box ticked when you connected, and
your confirmation in the conversation. Claude asks before each change, every time.
Spending Smart AI transactions on an import always needs your explicit yes in the conversation.
Change or stop access
You want to… | Do this |
Allow more, or fewer, kinds of change | Disconnect VAT4U in Claude's connector settings, connect again and tick a different set of boxes |
Stop Claude using VAT4U | Disconnect VAT4U in Claude's connector settings |
Stop a user in your organisation from using the connector | Ask VAT4U support to remove their Use AI Assistant permission. Access stops within about a minute, even if they are still connected |
You stay connected while you use the connector. If you do not use it for 30 days, Claude asks you to sign in to VAT4U again.
Good to know
Large expense searches can take up to a minute. For totals and breakdowns, ask for counts or a breakdown rather than a full list. Claude does this automatically when it can.
Very large answers are shortened. If a result is too large, it is cut short and Claude is told so. Ask a narrower question, for example one company, country or period.
Claude uses the same names as VAT4U. Statuses, countries and categories appear by name ("Ready", "Claimed", "Germany"), as in the app.
The AI assistant inside VAT4U is separate. It uses the same Use AI Assistant permission, but you do not need to connect anything to use it.
Troubleshooting
After signing in: "The AI assistant is not enabled for your VAT4U account."Your VAT4U user does not have the Use AI Assistant permission yet. Contact VAT4U support or your account manager to have it turned on, then click Connect again.
Claude says "This was not allowed when the VAT4U connector was authorized."You did not tick the box for that kind of change when you connected. The message names the box. Disconnect VAT4U in Claude's connector settings, connect again and tick it, or make the change in VAT4U yourself.
Claude says "Your VAT4U sign-in has expired" or "Your VAT4U connection could not be verified." Reconnect VAT4U in Claude's connector settings and sign in again. This happens after 30 days without using the connector, or if your access was withdrawn.
Claude cannot find a company you know exists. Claude only sees companies your VAT4U user has access to. Check that you can see the company when you sign in to VAT4U yourself. If you can, try the company's full legal name.
The upload page says "Upload not available". The page gives the reason. Usually the link was already used, has passed its 30 minutes, was opened while signed in as a different VAT4U user, or you can no longer add expenses to that company. Ask Claude for a new link, or add the invoices from the Import page in VAT4U.
The upload page says "Please upload either one zip file, or the documents themselves — not both together." Choose either the separate documents or one zip file, not both together, and click Add these invoices again. The link is still usable.
The upload page says "Please choose up to 20 files at a time". Put the files into one zip file and upload that instead, or upload them in batches.
Some files were "not added". Only PDF, JPG, PNG and TIFF documents become expenses. Convert other files to PDF and upload them through a new link.
The import finished, but the expenses are empty. That is expected. An import adds the documents, and Smart AI fills in the details only if you agree. Ask Claude to fill them in, or run Smart AI on them in VAT4U.
A download link asks me to sign in, or says I am not allowed. Download links work only in a browser signed in to VAT4U as the person who asked for them, and only once, within 5 minutes. Sign in to VAT4U in that browser, then ask Claude for a fresh link.
The claim approval page says the request cannot be approved. The link was already used, was declined, has passed its 15 minutes, or something changed since Claude prepared the claim. Ask Claude to prepare the claim again.
Claude refuses a claim and lists problems. These are the same checks VAT4U's claim wizard applies, for example missing claimant details, a bank account not set up for claims, a representative without a power of attorney, a period that is too short, or less than 50 EUR of VAT. Fix them in VAT4U, then ask Claude again.
An answer is slow. Searching through many expenses can take up to a minute. Ask for a count or a breakdown instead of a full list, or narrow the search by company, country or period.