einvoice-mcp

einvoice_validate_zugferd

Read-onlyIdempotent

Extract and check the embedded XML in ZUGFeRD PDFs to validate invoice compliance with EN 16931.

Instructions

Validiert eine ZUGFeRD-PDF, indem das eingebettete XML extrahiert und geprüft wird.

Args: pdf_base64: Die ZUGFeRD-PDF als Base64-kodierter String.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "pdf_base64": "<pdf_base64>"
    },
    "name": "einvoice_validate_zugferd"
  }
}

Input Schema

Name	Required	Description	Default
`pdf_base64`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Aug 8, 2026

TDQS

A4/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds the method of validation (extracting embedded XML) but does not disclose potential failure modes or side effects. It is consistent with the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is one sentence plus an Args list, with no redundant text. It is front-loaded with the purpose and directly explains the parameter.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the simple tool with one parameter, a read-only annotation, and an output schema, the description covers the core purpose and input. It does not include usage comparisons, but for a basic validation tool, the essential information is present.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema has no description for pdf_base64, and the description's Args section provides the necessary meaning: the ZUGFeRD-PDF as a Base64-encoded string. This compensates for the 0% schema description coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool validates a ZUGFeRD-PDF by extracting and checking the embedded XML. This distinguishes it from sibling tools like einvoice_generate_zugferd and einvoice_validate_xrechnung, which deal with generation or a different validation format.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage for validating ZUGFeRD PDFs but does not explicitly state when to prefer this over alternatives. No mention of exclusions or comparison with sibling tools like einvoice_validate_xrechnung or einvoice_check_compliance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server