# VAT.SUPPORT — Full Machine Specification & API Reference for AI Agents

> Authoritative European Union & United Kingdom VAT Compliance, VIES Entity Validation, and Statutory Rate Determination Infrastructure.

## 1. Native Model Context Protocol (MCP) Server

- **Server URL:** `https://vat.support/api/mcp`
- **Protocol:** Model Context Protocol (MCP) v2024-11-05
- **Transport:** `streamable-http` (JSON-RPC 2.0 via HTTP POST)
- **Authentication:** Publicly accessible endpoints. Optional API key `X-API-Key` for high-throughput enterprise tiers.

### Tool 1: reverse_charge_certificate
Evaluates statutory eligibility under Art. 196 EU VAT Directive (2006/112/EC) for cross-border B2B supplies between EU Member States.
- Input Schema:
  ```json
  {
    "type": "object",
    "required": ["supplier_country", "customer_country"],
    "properties": {
      "supplier_country": { "type": "string", "description": "Supplier ISO-3166-1 alpha-2 code (e.g. 'DE')" },
      "customer_country": { "type": "string", "description": "Customer ISO-3166-1 alpha-2 code (e.g. 'IT')" },
      "customer_vat_id": { "type": "string", "description": "Customer VAT identifier including country prefix (e.g. 'IT12345678901')" },
      "service_type": { "type": "string", "enum": ["professional_services", "digital_services", "transport", "telecom", "event_admission"] }
    }
  }
  ```
- Output Schema:
  ```json
  {
    "verdict": "ELIGIBLE" | "INELIGIBLE",
    "legal_article": "Art. 196 EU VAT Directive",
    "rate_applied": 0.0,
    "customer_vies": { "valid": true, "name": "...", "address": "..." },
    "audit_token": "string",
    "verify_url": "https://snapshot.vat.support/v/..."
  }
  ```

### Tool 2: vat_number_check
Real-time entity validation against European Commission VIES and UK HMRC.
- Input Schema:
  ```json
  {
    "type": "object",
    "required": ["vat_id"],
    "properties": {
      "vat_id": { "type": "string", "description": "Full VAT ID including country code prefix (e.g. 'FR12345678901')" }
    }
  }
  ```
- Output:
  ```json
  {
    "valid": true,
    "country": "FR",
    "vat_id": "FR12345678901",
    "company_name": "ACME SAS",
    "address": "123 Rue de Paris, 75001 Paris",
    "consultation_number": "WAPIAE9281X",
    "timestamp": "2026-11-03T20:59:00Z"
  }
  ```

### Tool 3: vat_rate_lookup
Fetches statutory standard and reduced VAT rates from the European Commission TEDB database.
- Input Schema:
  ```json
  {
    "type": "object",
    "required": ["country"],
    "properties": {
      "country": { "type": "string", "description": "ISO-3166-1 alpha-2 country code (e.g. 'DE', 'FR', 'ES')" },
      "rate_type": { "type": "string", "enum": ["standard", "reduced", "super_reduced", "zero", "parking"], "default": "standard" }
    }
  }
  ```

### Tool 4: vat_registration_check
Evaluates whether a cross-border seller must register for local VAT or One Stop Shop (OSS) based on sales volume and destination countries.
- Input Schema:
  ```json
  {
    "type": "object",
    "required": ["country"],
    "properties": {
      "country": { "type": "string" },
      "customer_type": { "type": "string", "enum": ["B2C", "B2B", "MIXED"] },
      "annual_revenue_eur": { "type": "number" },
      "sale_countries": { "type": "array", "items": { "type": "string" } },
      "supply_types": { "type": "array", "items": { "type": "string" } }
    }
  }
  ```

### Tool 5: vat_compliance_full
Performs comprehensive 10-question EU VAT compliance gap audit and delivers a 0-100 compliance rating with statutory article citations.

---

## 2. Direct REST API Endpoints

### POST https://snapshot.vat.support/api/v1/public/reverse-charge
Direct HTTPS endpoint for non-MCP agents:
```bash
curl -X POST https://snapshot.vat.support/api/v1/public/reverse-charge   -H "Content-Type: application/json"   -d '{
    "supplier_country": "DE",
    "customer_country": "FR",
    "customer_vat_id": "FR12345678901"
  }'
```

---

## 3. IDE & AI Assistant Configurations

### Cursor (`.cursor/mcp.json`)
```json
{
  "mcpServers": {
    "vat-support": {
      "url": "https://vat.support/api/mcp",
      "transport": "streamable-http"
    }
  }
}
```

### Windsurf (`~/.codeium/windsurf/mcp_config.json`)
```json
{
  "mcpServers": {
    "vat-support": {
      "url": "https://vat.support/api/mcp",
      "transport": "streamable-http"
    }
  }
}
```

### Claude Desktop (`claude_desktop_config.json`)
```json
{
  "mcpServers": {
    "vat-support": {
      "command": "npx",
      "args": ["-y", "mcp-proxy", "https://vat.support/api/mcp"]
    }
  }
}
```