Quaderno MCP for AI. Automate global taxes and billing logic.
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Quaderno brings global tax compliance and invoicing directly into your AI workflow. Calculate sales tax, VAT, or GST for any region, issue professional invoices, and manage customer contact data using a single API connection.
Stop leaving money on the table; automate your entire billing cycle with confidence.
What your AI can do
Calculate taxes
Calculates the applicable tax rate (VAT, GST, etc.) and total amount for a given sale price and location.
Create contact
Registers a new customer contact by providing their email, first name, and last name.
Create transaction
Records a new sale transaction and issues an invoice using the provided contact ID and item details array.
The server calculates applicable sales tax rates (VAT, GST, etc.) instantly by inputting a price amount and a customer's location.
You can create new contacts, retrieve existing user details using get_contact, or modify specific fields with update_contact.
The server records a complete transaction and issues an invoice by accepting a structured JSON array of product items and prices.
You retrieve lists of all contacts (list_contacts), invoices (list_invoices), or recorded transactions (list_transactions) in the account.
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Quaderno MCP Server: 10 Tools for Finance & Billing
Use these tools to calculate global taxes, manage CRM records, and automate complex billing workflows directly through your AI client.
Make your AI actually useful.
Add this MCP to Claude, Cursor, or Windsurf and your AI stops guessing. It gets real tools to look things up, take action, and handle the stuff you keep doing by hand.
Start using Quaderno on VinkiusCalculate Taxes
Calculates the applicable tax rate (VAT, GST, etc.) and total amount for a given sale price and location.
Create Contact
Registers a new customer contact by providing their email, first name, and last name.
Create Transaction
Records a new sale transaction and issues an invoice using the provided contact ID...
Delete Contact
Permanently removes a specified customer contact record from the account. This...
Get Contact
Retrieves all stored details for a specific customer by their unique ID.
Get Invoice
Fetches the full details of an existing invoice record using its identifier.
List Contacts
Generates a list containing all current customer contacts stored in the Quaderno account.
List Invoices
Retrieves a paginated list of every invoice that has been issued through the system.
List Transactions
Generates a complete history log of all recorded transactions in the account.
Update Contact
Modifies existing information for a customer contact using a structured JSON payload.
Security and governance baked right in.
Pick your AI client below to get set up. Just create a Vinkius account, subscribe, and you're instantly up and running. We handle the entire backend infrastructure, delivering out-of-the-box support for HTTPS Streamable, SSE, and OAuth2—zero messy routing required.
Claude AI
Open Claude Settings
Go to claude.ai, click your profile icon, then navigate to Customize → Connectors.
Add Custom Connector
Click the "+" button and select Add custom connector. Paste your Vinkius endpoint URL:
https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp
Replace [YOUR_TOKEN_HERE] with your token
from cloud.vinkius.com. For OAuth-protected servers, expand
Advanced settings to add credentials.
Start a conversation
Open a new chat. The Quaderno integration is available immediately — no restart needed.
Choose How to Get Started
Build a custom MCP for your own tools, or connect a ready-made integration from our catalog.
Build Your Own
Turn any API into an MCP. Import a spec, define Agent Skills, or deploy with MCPFusion.
- Import from OpenAPI, Swagger, or YAML specs
- Create Agent Skills with progressive disclosure
- Deploy to edge with MCPFusion framework
- Built in DLP, auth, and compliance on every call
- Real time usage dashboard and cost metering
- Publish to catalog or keep private
Make Your AI Do More
Start with Quaderno, then connect any of our 5,000+ other servers whenever your AI needs more. One click, no limits.
- Use this MCP plus 5,000+ others, all in one place
- Add new capabilities to your AI anytime you want
- Every connection is secured and compliant automatically
- Track usage and costs across all your servers
- Works with Claude, ChatGPT, Cursor, and more
- New servers added to the catalog every week
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Works with Claude, ChatGPT, Cursor, and more
The Model Context Protocol standardizes how applications expose capabilities to LLMs. Instead of operating in isolation, your AI gains direct access to external platforms, live data, and real-world actions through secure, standardized connections.
This connection provides 10 powerful capabilities that interface natively with Claude, ChatGPT, Cursor, and other compatible AI platforms. No middleware. No custom integration required.
Billing shouldn't feel like juggling three different software dashboards.
Today, processing a single international order means logging into your CRM to verify the address. Then you open a separate spreadsheet or tax calculator to determine the correct VAT rate for that zip code. After confirming the math, you copy all the data and paste it into your accounting platform to finally generate an invoice.
With Quaderno MCP Server, those steps vanish. You ask your AI agent one question—'Invoice this sale.' The server handles the address validation (`get_contact`), calculates the tax instantly (`calculate_taxes`), and issues the final record (`create_transaction`). It’s one conversational flow.
Quaderno MCP Server: Manage contacts, invoices & taxes
The manual steps that disappear include switching between CRM UI and tax calculators. You no longer need to copy the customer's name from one window, verify the tax rate on a public website, and then re-enter everything into your accounting software.
Now, you keep all data—contact details, calculated taxes, and transaction records—within the context of your AI agent. It’s fully integrated financial intelligence.
What your AI can actually do with this
Your AI client connects directly to Quaderno's Quaderno server to handle global tax compliance, invoicing, and customer records right in your workflow. This single API connection lets you automate complex financial logic that used to require multiple systems.
Global Tax Calculation
The calculate_taxes tool calculates the applicable tax rate—whether it's VAT, GST, or something else—and figures out the total amount for any sale price and location. You input a cost and a customer's region, and the server instantly returns the correct tax breakdown. This means you know exactly what your final billed price needs to be before sending anything out.
Managing Customer Data (CRM)
The system manages all your client information through several specific functions. To add someone new, use create_contact; you just provide their email, first name, and last name, and the record gets registered immediately. If you already have a customer, get_contact pulls up all their stored details using their unique ID.
Need to change something—like an outdated phone number or address—you run update_contact, providing a structured JSON payload to modify existing fields.
When a contact is no longer needed in your system, you use delete_contact. Be careful with this one; that action permanently removes the customer record and can't be undone. To see who you've got on file, run list_contacts, which gives you an exhaustive list of every current customer profile stored in the account.
Invoicing and Transactions
The core function for billing is handled by create_transaction. When a sale happens, you use this tool to record the full transaction history. You pass it a structured JSON array detailing all product items and their prices, along with the customer's contact ID; the server handles recording that sale and issuing the official invoice simultaneously.
To check on an existing bill, get_invoice fetches the complete details of any specific invoice you point it toward using its unique identifier. If you need to audit a past billing cycle or review a previous sale, running list_invoices retrieves a paginated list of every single invoice that's ever been issued through the system.
For a deep dive into historical sales activity, use list_transactions; this generates a complete history log covering all recorded transactions in the account.
Comprehensive Auditing and Reporting
To keep your books clean, you can pull reports on every part of your data set. You run list_contacts to see every customer profile. For invoices, list_invoices gives you a paginated list of everything billed. Similarly, running list_transactions provides the full historical record of all recorded sales and payments. The system also lets you pull specific details using get_contact or get_invoice, ensuring you have the exact data point you need for any audit or report.
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Here's how it actually works
The bottom line is that you manage complex global financial logic by passing structured instructions—not just natural language—to the system.
Subscribe to the Quaderno server and authorize it using your dedicated API Key.
Instruct your AI agent (e.g., 'Calculate tax for $50 sold to France'). The agent runs calculate_taxes and returns the VAT rate and total due.
Use the returned data to issue a final invoice, calling create_transaction with the required contact ID and itemized JSON payload.
Who is this actually for?
E-commerce founders who sell internationally; Finance engineers building billing webhooks; and client success managers handling account updates. If your sales model involves multiple tax jurisdictions, you need this.
Uses the agent to prompt for taxes on new markets during a promotion launch, ensuring correct VAT/GST rates are applied before marketing materials go live.
Writes automated billing logic by using get_invoice and list_transactions to validate records without leaving the coding environment.
Quickly edits a client's misspelled billing address using update_contact, then immediately uses that updated data in create_transaction for a new order.
What Changes When You Connect
Tax compliance becomes immediate. Instead of manually checking tax rates for every country, the calculate_taxes tool runs in seconds, giving you the precise VAT/GST rate needed to complete a sale.
Keep your data clean with full CRM control. You can use get_contact, list_contacts, and update_contact to ensure client billing addresses are current before running any transaction.
Invoice generation is one step, not three. By calling create_transaction, you pass itemized goods and let the server handle both recording the sale and generating the official invoice.
Audit trails are always available. Never hunt through separate dashboards; use list_invoices or list_transactions to pull a clean history of every financial event, all in one prompt.
Cross-functional workflow: You can find an old client's details with get_contact, verify their billing status by running get_invoice, and then update them all before issuing the next bill.
See it in action
A new product launch requires global tax validation.
The E-commerce Founder wants to test pricing for a sale in Brazil. Instead of opening a separate calculator, they ask their agent: 'What are the taxes on $100 sold to São Paulo?' The agent runs calculate_taxes, returns the precise Brazilian rate, and allows the founder to confirm the final price instantly.
A client changes address mid-billing cycle.
The Client Success Manager notices a typo in a client's billing zip code. First, they run get_contact to verify the ID. They then use update_contact to fix the record. Finally, they call create_transaction, guaranteeing the new invoice uses the correct address.
Auditing a high-value account.
The Finance Engineer needs to check all billing history for Account #12345. They use list_invoices and then follow up with list_transactions. This gives them a complete, chronological audit trail of every payment and credit.
Needing a full list of active clients.
The Sales team needs to pull contact data for an annual review. They use the agent to run list_contacts, receiving a machine-readable JSON array that they can immediately feed into another system or analysis tool.
The honest tradeoffs
Assuming taxes are fixed.
Sending a prompt like, 'Send an invoice for $50 to Berlin.' The agent fails because it doesn't know the correct VAT rate or if the contact exists.
Always start with calculate_taxes first. Use the result of that tool call (e.g., 19% VAT) and then include those precise numbers when calling create_transaction. This guarantees accuracy.
Creating a transaction without pre-verifying contact data.
Calling create_transaction with an ID or email that doesn't exist. The process halts, and the agent cannot proceed because the primary record is missing.
Always run get_contact or list_contacts first to validate the customer's ID. If the data looks wrong, use update_contact before attempting any financial actions.
Manually updating records and forgetting history.
A user updates a contact address but doesn't know how to prove the change was recorded or when it happened. They only see the new data, not the audit trail.
After using update_contact, immediately follow up with get_invoice or list_transactions. This proves that the updated record is now feeding into live financial records.
When It Fits, When It Doesn't
Use this server if your business involves international sales, complex billing logic, or multi-jurisdictional tax requirements. You need it when a single sale requires calculating taxes and updating CRM data simultaneously.
Do NOT use this if you only handle simple, domestic transactions where the tax rate is always fixed (e.g., 7% state tax). In that case, a simpler form submission tool might suffice. If your goal is just to store names and emails without billing capability, basic contact management tools work fine, but they won't generate invoices or calculate taxes.
Questions you might have
Where do I find my Quaderno API Key and URL? +
Log in to your Quaderno account. Your API URL is simply your domain up top in the browser bar (e.g., https://mycompany.quadernoapp.com). To get the API Key, navigate to Settings > API Keys (or Developers), and copy your private key. Do not share this key as it carries full access. Paste both credentials below.
Can it calculate exact taxes dynamically before a sale? +
Yes! Use the calculate_taxes tool and just provide the AI with a country code, postal code, and base amount. Quaderno's world-class engine evaluates real-time location-based tax nuances (VAT, GST) and returns the exact fraction needed.
Can I draft custom test invoices natively in chat? +
Absolutely. You can use create_transaction. Instruct your agent to format a JSON array with products and amounts, linking to a specific contact_id. The server submits this array to Quaderno and records the fully realized transaction safely.
Will deleting a contact via the AI remove them permanently? +
Yes. The delete_contact operation relies heavily on standard destructive API instructions. Running this means the contact is gone entirely from the Quaderno dashboard. Always review deletion queries cautiously before approving execution.
When I use `list_invoices`, can I filter results by date range or customer name? +
Yes. You pass filtering parameters directly to the list_invoices tool in your prompt. This lets you narrow down records—for example, showing only invoices from Q2 of this year—before needing a specific invoice ID.
If I use `create_transaction`, what should I watch out for if the required product details are missing? +
The system returns a structured payload detailing the validation failure. It specifies exactly which required fields—like contact ID or itemized prices—are missing or malformed, helping you fix the input immediately.
When running `update_contact`, do I have to provide every single piece of customer information? +
No. You only need to pass a JSON payload containing the specific fields you want changed. The server ignores any contact details that are not included in your update request.
When I use `calculate_taxes`, does it handle complex cross-border tax rules, like digital services or exemptions? +
Yes. Quaderno handles global tax compliance by checking the destination region against current law. It calculates VAT, GST, and other localized requirements specific to international sales.
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