Polish e-invoicing MCP: KSeF API v2, FA(3)/FA(2) XML, Peppol BIS 3.0, NIP/REGON validation.
Connect MCP to Claude, Cursor or any other MCP client and it stops being a tab you switch to. Polish e-invoicing MCP: KSeF API v2, FA(3)/FA(2) XML, Peppol BIS 3.0, NIP/REGON validation. The mcp mcp server is what makes that connection.
A Python MCP server providing tools for Polish electronic invoicing compliant with KSeF (FA(2)) and Peppol BIS Billing 3.0 / EN 16931. It enables AI agents (Claude, IDEs) to generate, validate, and submit invoices to the Krajowy System e-Faktur (KSeF), as well as validate Polish tax identifiers (NIP and REGON).
The toolset is worth reading before you wire it up, because it tells you what the integration is really for:
References — The References tool exposed by this servermcp-ksef-pl on PyPI is all you need. Most clients run it directly, so configuration is a few lines and a restart.
Configuration is passed through the environment: KSEF_ENVIRONMENT, KSEF_SESSION_TOKEN, KSEF_NIP. Treat anything key-shaped as a real credential — scope it to the minimum the server needs, and rotate it if it ever lands in a shared config.
Among the developer tooling options, the useful question is rarely "what can it do" but "what does it cost you to run" — permissions, credentials, and how much of your context its toolset consumes. MCP's toolset — References — is a fair guide to whether it matches your workflow. It is maintained by cmendezs; worth a glance at recent repository activity before you build anything load-bearing on it.
SyncDev reviews every entry in this directory against the project's own documentation before publishing, and revisits them as servers change.
| Tool | What it does |
|---|---|
| References | The References tool exposed by this server. |
{
"mcpServers": {
"ksef-pl": {
"command": "uvx",
"args": ["mcp-ksef-pl"],
"env": {
"KSEF_ENVIRONMENT": "your-value",
"KSEF_SESSION_TOKEN": "your-value",
"KSEF_NIP": "your-value"
}
}
}
}Add to claude_desktop_config.json, then restart Claude Desktop.
| Variable | Description | Required |
|---|---|---|
| KSEF_ENVIRONMENT | Configuration value read at startup. | Optional |
| KSEF_SESSION_TOKEN | Credential the server authenticates with. | Yes |
| KSEF_NIP | Configuration value read at startup. | Optional |
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