Finance & Accounting · 44API + Claude
44API MCP with Claude: Validate VAT Numbers and Company Details Faster
The short answer
Claude works with 44API through the Model Context Protocol (MCP), an open standard that lets Claude securely use software with permissions you control. Once connected with an API key, Claude can validate VAT and tax identifiers, return company details and manage IP whitelists when asked in everyday language, with people approving sensitive changes.
What is 44API?
44API is an API service for validating VAT and tax identifiers and returning company details. Finance teams, accounts payable staff, procurement officers, compliance teams and developers use it to confirm that suppliers and customers are registered correctly before payments are made or contracts are signed. It also lets administrators manage which IP addresses are allowed to access their account, helping keep data access tightly controlled.
How Claude connects to 44API through MCP
The Model Context Protocol (MCP) is an open standard that works like a universal adapter between Claude and other software. It allows Claude to use a tool securely, reading information and taking actions, but only within the permissions the organisation has set. Instead of copying data between windows, your team can ask Claude a question and let it reach the tool directly.
Once 44API is connected through its MCP server or direct API using your API key, Claude can typically validate a VAT number, check a tax identifier, look up company details for a registered business and review or update IP whitelist entries. Requests are made in natural language, so a finance team member can ask for a check without learning the API's technical structure.
Permissions and approvals keep people in charge. Access is granted with least-privilege settings, so Claude only sees and does what is needed for the task. Consequential actions, such as changing an IP whitelist, can be set to require human approval, and every action is recorded in an audit log for review.
What you can automate
Supplier onboarding checks
When a procurement officer adds a new supplier, Claude can validate the supplier's VAT number and retrieve registered company details in one request. The results are summarised for the onboarding form, reducing manual lookups and helping catch typos or mismatched names before the supplier is set up in the finance system.
Customer invoice verification
Accounts receivable teams can ask Claude to confirm that a customer's tax identifier is valid before issuing an invoice. This supports correct VAT treatment on invoices and reduces the risk of rejected or corrected documents later in the billing cycle.
Bulk tax ID review
Compliance staff often need to check hundreds of records at once, such as after a vendor data clean-up. Claude can work through a list of identifiers, flag invalid or inconsistent entries and produce a summary table that a reviewer can check before any records are changed.
Access control for IP whitelists
IT administrators can ask Claude to list current IP whitelist entries or propose an addition for a new office or contractor. Because changes can require approval, the administrator stays in control while the routine lookup and paperwork are handled quickly.
Due diligence research
Before a partnership or acquisition, analysts can ask Claude to pull registered company details for a set of target businesses. Claude organises the results into a comparison note, saving time on repetitive data gathering so the team can focus on the commercial judgement.
An end-to-end workflow: New supplier verification to ERP record
TriggerA procurement request is approved in Microsoft 365 and a new supplier form is submitted.
Claude reads the supplier details from the approved form in Microsoft 365.
Claude validates the supplier's VAT number through 44API and checks the tax identifier.
Claude retrieves registered company details and compares the legal name and address with the form.
Claude flags any mismatch in a short summary and sends it to the finance reviewer for approval.
Once approved, the verified supplier record is created in the organisation's ERP system with an audit trail.
OutcomeSupplier records are created with checked tax data, typically reducing manual lookup time and the number of errors that reach accounts payable. Results depend on each organisation's processes.
How we set it up
Free automation audit
We review your finance, procurement and IT workflows to find where VAT checks, company lookups and access changes take the most time. You receive a clear list of the workflows worth automating.
Secure connection with an API key
We connect Claude to 44API using your API key, stored securely and scoped to the minimum access needed. Where a direct API is used, the connection is built to the same least-privilege standard.
Workflow design
We design the end-to-end process across 44API and your other systems, such as Microsoft 365, your CRM, ERP or ticketing tool. We agree which actions run automatically and which require a person's approval.
Testing with real cases
We test the workflow against past supplier and customer records to confirm accuracy and spot edge cases. Findings are reviewed with your team before anything goes live.
Launch, monitoring and training
We launch with monitoring and audit logs in place, then train your finance, procurement and IT staff on how to use Claude with 44API day to day.
Who benefits
- Finance director
- Gets checked tax data flowing into records, with a clear audit trail for review.
- Accounts payable manager
- Spends less time on manual VAT and company lookups during supplier setup.
- Procurement lead
- Onboards suppliers faster with verified legal names and registration details.
- IT administrator
- Handles IP whitelist requests quickly while keeping approval controls in place.
Security and control
- Least-privilege API key access, so Claude only reaches what each task requires.
- Human approval for consequential actions such as changing IP whitelist entries.
- Audit logs that record every request Claude makes to 44API.
- Clear separation between checking data and writing it into your core systems.
- Regular review of access permissions and API key rotation as your team changes.
For teams in the US, UK, India and the Middle East
Organisations in the United States and the United Kingdom can host the workflow in a region that matches their data expectations, and we configure it to align with applicable privacy and financial record rules. Businesses in India can keep processing within India to meet the Digital Personal Data Protection Act, 2023. Companies in the UAE and Saudi Arabia can choose hosting that supports their local data protection requirements. We select the hosting region during design so the solution meets your specific obligations.
Learn more about Claude and MCP
Anthropic's AI model and assistant.
Secure links between Claude and business tools.
How engineers build and change software with Claude.
Hosted agents that run multi-step work.
The open standard Claude uses to connect to tools.
Frequently asked questions
What does the 44API MCP server do?
The 44API MCP server lets Claude connect to 44API in a standard way. Through it, Claude can validate VAT numbers, verify tax identifiers, fetch company details and manage IP whitelists when asked in natural language. It acts as a secure bridge, so your team does not need to write code to use these checks.
Is connecting 44API to Claude secure?
Security is built into the design. Access uses an API key with least-privilege settings, so Claude only reaches the functions a task needs. Consequential actions can require human approval, and every request is logged. We also advise on key storage and rotation to keep the connection well controlled.
What can Claude do with 44API once connected?
Typically, Claude can validate a VAT number, check a tax identifier, retrieve registered company details for a business, and review or update IP whitelist entries. It can also work through lists of records and summarise the results, while your staff decide what happens next.
How long does setup take?
Timelines depend on the number of workflows and the systems involved. A single, well-defined workflow is often connected and tested within a few weeks after the free audit. More complex, multi-system automations take longer, and we agree a timeline with you before any build begins.
Which plan or permissions do I need?
You need an active 44API account and an API key with the access level your workflow requires. The exact permissions depend on whether you need lookups only or also IP whitelist management. We confirm the required access during the audit so you only grant what is necessary.