Peppol Validator API & Agent Skill

API endpoint

Option 1: Raw XML body

Send the XML directly as the request body with a Content-Type: application/xml header.

curl -X POST https://peppolvalidator.com/api/v1/validate \
  -H "Content-Type: application/xml" \
  -d @invoice.xml

Option 2: Multipart form data

Upload the file as a file field in a multipart request.

curl -X POST https://peppolvalidator.com/api/v1/validate \
  -F "file=@invoice.xml"

JavaScript / Node.js

const xml = fs.readFileSync("invoice.xml", "utf-8");

const res = await fetch("https://peppolvalidator.com/api/v1/validate", {
  method: "POST",
  headers: { "Content-Type": "application/xml" },
  body: xml,
});

const result = await res.json();
console.log(result.status); // "valid" | "invalid" | "error"

Python

import requests

with open("invoice.xml") as f:
    xml = f.read()

res = requests.post(
    "https://peppolvalidator.com/api/v1/validate",
    headers={"Content-Type": "application/xml"},
    data=xml,
)

result = res.json()
print(result["status"])  # "valid" | "invalid" | "error"

Response format

Example response

{
  "fileId": "a1b2c3d4-...",
  "filename": "invoice.xml",
  "status": "invalid",
  "format": "ubl",
  "specification": "Peppol BIS Billing 3.0",
  "sellerCountry": "BE",
  "invoiceNumber": "INV-2026-001",
  "errors": [
    {
      "id": "1",
      "severity": "error",
      "rule": "BR-16",
      "location": "/Invoice",
      "message": "An Invoice shall have at least one Invoice line (BG-25)."
    }
  ],
  "warnings": [
    {
      "id": "2",
      "severity": "warning",
      "rule": "PEPPOL-EN16931-R080",
      "location": "/Invoice/cac:TaxTotal",
      "message": "Tax category tax amount must equal..."
    }
  ],
  "infos": [],
  "validatedAt": "2026-02-17T12:00:00.000Z",
  "resultsUrl": "https://peppolvalidator.com/r/a1b2c3d4-..."
}

Quickstart

HTTP status codes

Error codes

Retry guidance

Authentication

CORS

XML to PDF conversion

cURL example

curl -X POST https://peppolvalidator.com/api/v1/xml-to-pdf \
  -H "Content-Type: application/xml" \
  -d @invoice.xml \
  -o invoice.pdf

Response

Returns application/pdf with a Content-Disposition: attachment header. On error, returns JSON with an error field and a 400 status code. Supports both raw XML body and multipart form upload (same as the validation endpoint).

MCP Server

Available tools

Configuration

Add this to your MCP client configuration (e.g. claude_desktop_config.json or .cursor/mcp.json):

{
  "mcpServers": {
    "peppol-validator": {
      "url": "https://peppolvalidator.com/mcp"
    }
  }
}

Discovery

Test it

curl -X POST https://peppolvalidator.com/mcp \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

Agent Skill

Download and place in your project. For Claude Code, use .claude/skills/. For other agents, use .agents/skills/.

.claude/skills/validating-peppol-invoices/SKILL.md

Or create the file manually with these contents:

---
name: validating-peppol-invoices
description: Validates Peppol UBL XML invoices and credit notes
  against EN16931 (CEN) and Peppol BIS Billing 3.0 schematron
  rules via the Peppol Validator API. Use when validating
  e-invoices, checking Peppol compliance, debugging UBL XML
  validation errors, or verifying invoices before sending via
  the Peppol network.
---

# Validating Peppol Invoices

POST XML to the Peppol Validator API and parse the JSON result.

## Endpoint

\`POST https://peppolvalidator.com/api/v1/validate\`

Send raw XML with \`Content-Type: application/xml\`:

```bash
curl -X POST https://peppolvalidator.com/api/v1/validate \
  -H "Content-Type: application/xml" \
  -d @invoice.xml
```

Returns JSON with status ("valid" / "invalid" / "error"),
errors, warnings, and invoice metadata.

What your agent can do with it

• •Validate XML invoices during development and flag issues inline
• •Run validation as part of CI/CD before deploying invoice generation code
• •Debug Peppol validation errors by examining rule IDs and locations
• •Verify fixes by re-validating after changes

Common questions