# XRechnung Validator (npm · xrechnung-validator-mcp)

Validate XRechnung XML and ZUGFeRD / Factur-X PDFs with the free checkxrechnung.com API.

- Trust score: 72/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-23

## Components

- npm · `xrechnung-validator-mcp`: 72/100 (this document), [markdown](https://verifymcp.io/servers/wenboteng-xrechnung-validator/xrechnung-validator-mcp.md), [page](https://verifymcp.io/servers/wenboteng-xrechnung-validator/xrechnung-validator-mcp)

## Channel facts

- Registry: `npm`
- Package: `xrechnung-validator-mcp`
- Version: `0.2.0`
- Transport: `stdio`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-10-23.

- **Supply Chain Security**: 98/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - No install/post-install scripts declared.
  - 30 of 93 dependencies flagged as unhealthy.
- **Provenance & Transparency**: 45/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 2 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 74/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 473 tokens (~157/item across 3 items; 3 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 13/100
  - Stability observed for 4 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
  - Structured output schemas are declared (100% of tools); any adoption earns full credit.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 3 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 3 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### How do I install the XRechnung Validator MCP server?

XRechnung Validator runs locally as an npm package, launched with npx -y xrechnung-validator-mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add wenboteng-xrechnung-validator -- npx -y xrechnung-validator-mcp
```

### Cursor

```json
{
  "mcpServers": {
    "wenboteng-xrechnung-validator": {
      "command": "npx",
      "args": [
        "-y",
        "xrechnung-validator-mcp"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "wenboteng-xrechnung-validator": {
      "command": "npx",
      "args": [
        "-y",
        "xrechnung-validator-mcp"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add wenboteng-xrechnung-validator -- npx -y xrechnung-validator-mcp
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "wenboteng-xrechnung-validator": {
      "type": "local",
      "command": [
        "npx",
        "-y",
        "xrechnung-validator-mcp"
      ],
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add wenboteng-xrechnung-validator --command npx --arg -y --arg xrechnung-validator-mcp
```

### Hermes

```yaml
mcp_servers:
  wenboteng-xrechnung-validator:
    command: "npx"
    args: ["-y", "xrechnung-validator-mcp"]
```

### Netclaw

```json
{
  "McpServers": {
    "wenboteng-xrechnung-validator": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "xrechnung-validator-mcp"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add wenboteng-xrechnung-validator -t stdio -c npx -a -y xrechnung-validator-mcp
```

### Other

```json
{
  "mcpServers": {
    "wenboteng-xrechnung-validator": {
      "command": "npx",
      "args": [
        "-y",
        "xrechnung-validator-mcp"
      ]
    }
  }
}
```

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-10-23 (score 72, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-21 (score 71, +16)

- [security improvement] Malware scan: unverified → pass

### 2026-10-20 (score 55, −1)

- [security improvement] Malware scan: unverified → pass
- [functional regression] Schema quality: pass → fail
- [functional improvement] Stability: unverified → 0.03
- [functional] Package version: 0.1.0 → 0.2.0

### 2026-10-19 (score 56)

First indexed and scored.

## MCP tools (3)

### `validate_xrechnung` (~153 tokens)

Validate XRechnung

Validate one XRechnung XML document (UBL or CII) or ZUGFeRD PDF. The file is uploaded to the free keyless API POST https://checkxrechnung.com/v1/validate. Limits: 50 requests per IP per UTC day, 10 per minute, 5 MB. The service reports persisted: false. Provide exactly one of file_path or xml. Returns valid plus errors with rule_id and rule_url.

Input parameters:

- `file_path` (string): Path to an XRechnung XML file or a ZUGFeRD PDF. Resolved by this process.
- `xml` (string): XRechnung XML (UBL or CII) as a string. Use this or file_path.

Output parameters:

- `bytes` (number)
- `errors` (array)
- `fileName` (string)
- `hasXml` (boolean)
- `invoiceType` (string)
- `persisted` (boolean)
- `summary` (object)
- `syntax` (string)
- `valid` (boolean)
- `versions` (object)

### `validate_zugferd` (~208 tokens)

Validate ZUGFeRD / Factur-X

Validate one ZUGFeRD or Factur-X PDF. The file is uploaded to POST https://checkxrechnung.com/v1/zugferd/validate. Checks PDF/A-3 basics (veraPDF when installed, otherwise a labelled structure check), extracts factur-x.xml, zugferd-invoice.xml or xrechnung.xml, detects the profile (MINIMUM, BASIC WL, BASIC, EN16931, EXTENDED, XRECHNUNG) and validates the XML with the EN 16931 CII Schematron. Profile XRECHNUNG also runs the XRechnung CII Schematron. Same free limit as validate_xrechnung (shared counter): 50 per IP per UTC day, 10 per minute. PDF limit 10 MB. Returns valid, profile, and errors with rule_id and rule_url.

Input parameters:

- `file_path` (string, required): Path to a ZUGFeRD or Factur-X PDF. Resolved by this process.

Output parameters:

- `embeddedName` (string)
- `errors` (array)
- `fileName` (string)
- `pdfa` (object)
- `profile` (string)
- `valid` (boolean)

### `extract_zugferd` (~112 tokens)

Extract ZUGFeRD / Factur-X XML

Extract the embedded invoice XML and a JSON summary from a ZUGFeRD or Factur-X PDF. Uploads the file to POST https://checkxrechnung.com/v1/zugferd/extract. Same free limit as validate_xrechnung (shared counter). PDF limit 10 MB. ok means an XML attachment was found. The xml field is the raw document.

Input parameters:

- `file_path` (string, required): Path to a ZUGFeRD or Factur-X PDF. Resolved by this process.

Output parameters:

- `embeddedName` (string)
- `fileName` (string)
- `ok` (boolean)
- `profile` (string)
- `summary` (object)
- `xml` (string)

## Diagnostics

Captured diagnostic sections: Provenance, Dependencies. The full working is on the page: https://verifymcp.io/servers/wenboteng-xrechnung-validator/xrechnung-validator-mcp#diagnostics

## Score history

- 2026-10-23: 72
- 2026-10-22: 71
- 2026-10-21: 71
- 2026-10-20: 55
- 2026-10-19: 56

## Common questions

### What is the XRechnung Validator MCP server?

XRechnung Validator is an MCP server listed in the public MCP registry as io.github.wenboteng/xrechnung-validator. Validate XRechnung XML and ZUGFeRD / Factur-X PDFs with the free checkxrechnung.com API. This page covers its npm package (xrechnung-validator-mcp).

### Is the XRechnung Validator MCP server safe to use?

XRechnung Validator scores 72 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 23 October 2026. It declares no install or post-install scripts. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the XRechnung Validator MCP server expose?

XRechnung Validator exposes 3 tools: validate_xrechnung, validate_zugferd, extract_zugferd. Their descriptions and schemas cost roughly 473 tokens of context every time the server is loaded.

### Is the XRechnung Validator MCP server still maintained?

XRechnung Validator is still listed as active in the MCP registry. We last reached this channel on 23 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

### What licence is the XRechnung Validator MCP server under?

XRechnung Validator declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.

## Links

- npm package: https://www.npmjs.com/package/xrechnung-validator-mcp
- Socket report: https://socket.dev/npm/package/xrechnung-validator-mcp
- Repository: https://github.com/wenboteng/xrechnung-validator
- Website: https://checkxrechnung.com/
- Changelog RSS feed: https://verifymcp.io/servers/wenboteng-xrechnung-validator/xrechnung-validator-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/wenboteng-xrechnung-validator/xrechnung-validator-mcp.json
- HTML version of this page: https://verifymcp.io/servers/wenboteng-xrechnung-validator/xrechnung-validator-mcp