ChatGPT
Remote MCP · OAuthVAT evidence, in your conversation.
Validate VAT and EORI numbers and retrieve audit evidence in ChatGPT. VAT rates are available as an additional tool.
Explore ChatGPTVIESAC × your AI workspace
VAT and VIES validation. Audit evidence. One MCP server.
Connect your AI assistant or agent to VIESAC today. Validate VAT/GST identifiers through EU VIES and supported national registries, check EORI numbers, create compliance audits and retrieve evidence through one production-ready Model Context Protocol server. VAT rates are also available.
Your VIESAC account. Your selected organization. Permissions you control.
Available now · Remote MCP server
Connect VIESAC manually today.
Use the public endpoint in any client or agent runtime that supports remote MCP over Streamable HTTP and OAuth. The model can vary; the host must support this connection. No app directory listing is required.
Production MCP endpoint
https://mcp.viesac.euTransport: Streamable HTTP
Authentication: OAuth with PKCE
Setup: automatic discovery and dynamic client registration
Cursor / compatible client configuration
{
"mcpServers": {
"VIESAC": {
"url": "https://mcp.viesac.eu"
}
}
}Client configuration names vary. Gemini CLI uses httpUrl instead of url for this transport.
- 1. Add a remote MCP server
Name it VIESAC and enter the endpoint. Choose Streamable HTTP and OAuth. No local VIESAC server is needed.
- 2. Authorize your account
Select Connect or Authenticate, sign in on viesac.eu, choose your organization and review read/audit permissions. OAuth-capable clients discover the sign-in settings automatically.
- 3. Run a validation
Ask: “Validate VAT DE129274202 without creating an audit. Show the result source and check time.” Request an audit explicitly when you need evidence.
Both files describe the public server without credentials. Configure model access separately where required. Never paste passwords or tokens into a conversation.
Choose your workspace
Connect from your preferred MCP client.
The VIESAC MCP endpoint is live. Use the same service from compatible assistants, coding tools and custom AI agents. You do not need to wait for an app directory listing to configure a direct MCP connection.
Cursor
Remote MCP · OAuthCheck identifiers where you work.
Bring VAT validation and your organization’s audit evidence into Cursor through a live remote MCP connection. VAT rates are also available.
Explore Cursor
Gemini CLIOne endpoint. A new way to ask.
Connect Gemini CLI to the live VIESAC MCP server for VAT validation and audit evidence. Use supported Google model credentials; this is separate from the Gemini consumer app.
Explore Gemini CLIBuilt on MCP
A shared connection, with access you control.
MCP lets compatible assistants discover VIESAC tools and request results. You sign in to VIESAC and choose the organization whose data the assistant may access.
- 01 · Choose your assistant
Follow the platform-specific guide and check its availability.
- 02 · Connect VIESAC
Review read and audit permissions before approving access.
- 03 · Ask for what you need
Start with a quick check. Request a credit-consuming audit explicitly.
From a quick check to evidence
Ask a question. Get a useful answer.
VAT & EORI validation
Check identifiers through EU VIES and supported national registries. Quick checks return a status, not company evidence.
“Check VAT DE129274202 without creating an audit.”
Audit evidence
Explicitly request a VAT, EORI or combined audit. Retrieve references and available certificates from your organization’s history.
“Find my latest VAT audit and its evidence link.”
VAT rates
Look up standard, reduced and supported regional rates, with the source information returned by VIESAC.
“What VAT rates are available for Germany?”
Coverage varies by country and tool. A registry outage is not an invalid result. Explore supported countries
MCP tool reference
Validation first. Audits when you need evidence.
The server exposes nine tools. Your client discovers their complete input schemas through MCP. Registry coverage and returned fields depend on the identifier and the source.
| Tool | Input | Result and behavior |
|---|---|---|
validate_vat | vat, with country prefix | VAT/GST validation through EU VIES or a supported national registry. No company evidence or audit record. Inspect validation_scope, registry_checked and registration_valid when returned: format or checksum validity alone does not confirm registration. |
validate_eori | eori; optional country_code | EU or UK customs identifier validation. Does not create an audit. |
create_audit | type; VAT/EORI identifiers; optional references | Creates a VAT, EORI or combined audit and consumes existing credits. Returns an audit reference and available evidence. Company data, consultation numbers and certificates depend on registry response and plan. |
get_audit | reference_number | Retrieve an audit and available certificate links from the connected organization. |
list_audits | Optional identifier, type, country, date or business-reference filters | Retrieve the connected organization’s audit history. |
search_partners | q | Search counterparties in the connected organization’s records, not a global company directory. |
check_quota | No input | Inspect the connected account’s plan and remaining quota before credit-consuming work. |
get_vat_rates | country | Additional tool: standard, reduced and supported regional VAT rates. |
list_vat_rates | Optional country and eu_only filters | Additional tool: list available VAT rate information. |
A quick validation is a status check, not a compliance certificate. A registry outage is not an invalid identifier. Cached responses keep their original check time. For registry evidence, explicitly request an audit and inspect the resulting record.
Your account, connected securely
Clear permissions. Existing VIESAC plans.
Sign in on viesac.eu, choose your organization and review access. Never paste your password, API key or access token into a conversation. Revoke a connection from your VIESAC API keys page.
Create a VIESAC accountRead access
Quick validation, your connected organization’s audit history, quota and VAT rates.
Audit access
Allows creating audits on request. One VAT or EORI audit uses 1 audit credit; a combined audit uses 2. Optional monitoring creates additional audits on its schedule.
Plans and billing
VIESAC limits apply. Purchase plans and credits on viesac.eu, outside your assistant. Identifiers and requested audit data are sent to VIESAC; usage is logged against your account.
Good to know
Before you connect.
Can I connect to the VIESAC MCP server now?
Yes. The production endpoint is https://mcp.viesac.eu. Use a client that supports remote MCP over Streamable HTTP and OAuth, then sign in to your VIESAC account. Directory approval is not required for direct MCP configuration.
Does a quick check create an audit?
No. Quick validation does not create audit evidence or consume audit credits. Account validation limits still apply. Request an audit explicitly when you need evidence.
Can the assistant search every company?
No. Audit history and counterparty search are scoped to your connected organization. They are not a worldwide company directory.
Does MCP work with any AI model?
The connection is made by the MCP client or agent runtime, not the model alone. Compatible remote MCP clients can connect to VIESAC regardless of the model they use. Each host has its own setup, authentication support and account requirements.
Optional app directories
Direct connection now. Directory listings to follow.
These application statuses do not change the availability of the production MCP server.
ChatGPT
App in reviewThe VIESAC app has been submitted to OpenAI. Public directory access is pending review; submission does not guarantee approval.
Cursor
Marketplace in reviewThe Cursor marketplace application is in review. Direct MCP connection has been verified and is available independently of the marketplace listing.
Gemini CLI
CLI verification pendingGemini CLI configuration is prepared; end-to-end model verification is pending supported Google API access. Our Google Connected Apps access application is also pending, as a separate process. Neither is a published Gemini app.