DATEV EXTF — Claude Code MCP server: what it does, how to install
Validates and generates DATEV EXTF accounting files right on your machine. Pinpoint import errors in booking batches without sending financial records over the network.
claude mcp add datev-extf -- npx -y @seamless-engineering/datev-extf-mcpWhat DATEV EXTF does
This MCP server inspects accounting batches (Buchungsstapel) and customer or vendor records (Debitoren/Kreditoren). When DATEV rejects an incoming file, the tool pinpoints the exact line, column, and cause. It flags common formatting mishaps, including dots in currency values, absent leading zeros in record dates, or incorrect tax keys on automated accounts. Diagnoses come in English or German.
Built-in tools include validate_datev_extf, explain_datev_finding, list_datev_columns, and write_buchungsstapel for format version 13 in Windows-1252 encoding. The setup requires Node.js 20 or higher. Supplying absolute file paths avoids path resolution issues tied to the server process directory. The server concentrates strictly on formatting rules, so it never reviews bookkeeping logic or tax law correctness.
What it helps with
- diagnose rejected DATEV accounting batch imports
- generate valid
BuchungsstapelCSV files in Windows-1252 encoding - inspect customer and vendor master data files for formatting errors
- retrieve index positions for 125 booking or 254 ledger columns
Example prompts for the agent
- Validate
/Users/alex/data/EXTF_Buchungsstapel.csvand report formatting issues - Explain why DATEV reports the
amount-dotfinding code - Build a Windows-1252
Buchungsstapelbatch from these raw transactions
How to install DATEV EXTF
Platform CLI
claude mcp add datev-extf -- npx -y @seamless-engineering/datev-extf-mcpPlatform CLI
codex mcp add datev-extf -- npx -y @seamless-engineering/datev-extf-mcpConfig file
{
"mcpServers": {
"datev-extf": {
"command": "npx",
"args": [
"-y",
"@seamless-engineering/datev-extf-mcp"
]
}
}
}Config file
{
"servers": {
"datev-extf": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@seamless-engineering/datev-extf-mcp"
]
}
}
}Platform CLI
gemini mcp add datev-extf npx -y @seamless-engineering/datev-extf-mcpStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about DATEV EXTF
How do I install DATEV EXTF in Claude Code?
Run claude mcp add datev-extf -- npx -y @seamless-engineering/datev-extf-mcp. Make sure your system has Node.js 20 or newer installed.
What does DATEV EXTF do?
It validates and outputs local DATEV-Format EXTF documents. The server explains rejected imports and formats new accounting batches according to official specifications.
Does the server verify tax account choices or bookkeeping validity?
No. It evaluates file syntax, field structures, and encodings, leaving tax decisions to the user and their tax advisor.
