Pop

pop-mcp

MCP (Model Context Protocol) server for POP — enabling LLMs to generate, submit, and manage Italian e-invoices (FatturaPA/SdI), Peppol, KSeF, ZUGFeRD/Factur-X, and PDF invoices directly from AI assistants.

npm: @getpopapi/pop-mcp · Remote: https://mcp.popapi.io/mcp

Remote MCP (HTTP) — fastest way to get started

Don't want to install anything? pop-mcp runs as a hosted, multi-tenant MCP server at:

https://mcp.popapi.io/mcp

Head to popapi.io to grab a license key, then point any MCP-speaking client at that URL with your key as a Bearer token. No local install, no POP_API_KEY env var, no build step — this is the recommended way to try pop-mcp for most people. Use the local stdio setup below only if you specifically need a Claude Desktop config running a process on your own machine.

How it works

This endpoint speaks MCP 2026-07-28, which is fully stateless: there is no initialize handshake and no session to open or track. Every request is self-contained — it names its own protocol version and capabilities — and the server answers it independently. Because of that, this is a multi-tenant endpoint: it never reads a fixed POP_API_KEY from its own environment. Every request must carry your own POP license key as a Bearer token:

Authorization: Bearer <your_license_key>

A missing or malformed Authorization header returns a 401 with error_code: "unauthorized_user" before any POP API call is made. An invalid-but-well-formed key is passed straight through to POP's API and surfaces whatever error POP returns (unauthorized_user, insufficient_level, etc.) — the server does not re-validate keys itself.

Any modern MCP HTTP client can connect: Claude (remote connector), the OpenAI Responses API, n8n, MCP Inspector, or a custom integration — not just Claude Desktop. All invoice, status, advanced, and onboarding tools are available; onboarding tools use their own onboarding_token per call and don't require the Bearer key.

Example with curl

Discover the server's supported protocol versions and capabilities (optional — clients can also just call tools/list or tools/call directly and handle a version-negotiation error inline):

curl -X POST https://mcp.popapi.io/mcp \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer your_license_key_here" \
  -H "MCP-Protocol-Version: 2026-07-28" \
  -H "Mcp-Method: server/discover" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "server/discover",
    "params": { "_meta": { "io.modelcontextprotocol/protocolVersion": "2026-07-28", "io.modelcontextprotocol/clientCapabilities": {} } }
  }'

List the available tools — every request is self-contained, so _meta (protocol version + client capabilities) travels on every call, not just the first one:

curl -X POST https://mcp.popapi.io/mcp \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer your_license_key_here" \
  -H "MCP-Protocol-Version: 2026-07-28" \
  -H "Mcp-Method: tools/list" \
  -d '{
    "jsonrpc": "2.0",
    "id": 2,
    "method": "tools/list",
    "params": { "_meta": { "io.modelcontextprotocol/protocolVersion": "2026-07-28", "io.modelcontextprotocol/clientCapabilities": {} } }
  }'

The tool catalog is identical for every license key, so tools/list and server/discover responses carry a one-hour public cache hint (ttlMs: 3600000, cacheScope: "public") — clients and gateways may cache them across tenants.

MCP-Protocol-Version and Mcp-Method are required on every request (per SEP-2243), and must match the body's _meta.protocolVersion and method exactly, or the server rejects the request with a 400 and JSON-RPC error -32020 (HeaderMismatch). tools/call requests additionally require an Mcp-Name header matching params.name.

Example with MCP Inspector

npx @modelcontextprotocol/inspector

Configure it to connect to https://mcp.popapi.io/mcp with header Authorization: Bearer <your_license_key>.

This endpoint runs as a Vercel serverless function (api/mcp.ts → src/mcpHandler.ts). To run it locally: npx vercel dev (requires vercel link to the project first).

What is POP?

POP is a cloud service for electronic invoice generation and delivery, supporting:

• 🇮🇹 Italian e-invoicing (FatturaPA/SdI) — compliant with D.Lgs. 127/2015
• 🇪🇺 Peppol — pan-European cross-border B2B invoicing (UBL 2.1)
• 📄 PDF invoices — branded, with email delivery
• ✅ Validation — fiscal codes, VAT numbers, document pre-submission checks
• 🗄️ Preservation — Italian legal archival (conservazione sostitutiva)

Tools Available (11 total)

Invoice Creation

Status & Retrieval

Validation & Advanced SdI

Prerequisites

• Node.js >= 20
• A POP license key
• For SdI/Peppol submission: active integration on your POP account (Basic/Growth plan)

Authentication

Get Your License Key

New to POP? Visit popapi.io to create your account and get your license key.

API-only users can activate their account and obtain a license_key with this flow:

1. Open https://popapi.io/otp-login/
2. Enter your email address
3. Receive a one-time password (OTP) by email and enter it
4. Complete the configuration wizard
5. Open https://popapi.io/ → Account > API
6. Copy the default generated license_key

Key Management

• Your account includes one default license_key, visible under Account > API
• You can generate additional keys linked to the same account from that same page
• Every license_key must be treated as a secret credential — do not commit it to source control

Recommended First Steps

1. Get your license_key
2. Test it with GET /account-profile
3. Send one document-generation request with a real payload
4. Add optional delivery integrations only after local generation works

Installation

From npm (recommended)

npm install -g @getpopapi/pop-mcp

From Source

git clone https://github.com/getpopapi/pop-mcp
cd pop-mcp
npm install
npm run build

Configuration

Set your POP license key as an environment variable:

export POP_API_KEY=your_license_key_here

Optional — use the staging environment:

export POP_ENVIRONMENT=staging

Claude Desktop Setup

Add to your claude_desktop_config.json:

If installed from npm:

{
  "mcpServers": {
    "pop": {
      "command": "pop-mcp",
      "env": {
        "POP_API_KEY": "your_license_key_here"
      }
    }
  }
}

If running from source:

{
  "mcpServers": {
    "pop": {
      "command": "node",
      "args": ["/path/to/pop-mcp/dist/cli.js"],
      "env": {
        "POP_API_KEY": "your_license_key_here"
      }
    }
  }
}

Config file locations:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

Tool Reference

The license_key is always injected automatically from POP_API_KEY — never pass it manually.

pop_create_sdi_invoice

Generate an Italian FatturaPA XML document. Optionally submit it to the SdI (Sistema di Interscambio).

MCP inputs:

Integration options for integration.use:

• "sdi-via-pop" or "sdi" — Submit via POP SdI
• "pop-to-webhook" — Deliver to a webhook (requires id)
• "fatture-in-cloud" — Deliver to Fatture in Cloud

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "user_agent": "pop-mcp",
  "user_agent_version": "1.0.0",
  "data": { "...invoice fields..." },
  "integration": { "use": "sdi-via-pop", "action": "create" }
}

integration is omitted when submit_to_sdi is false and no override is provided (XML-only generation).

pop_create_peppol_invoice

Generate a Peppol UBL 2.1 document. Optionally submit it to the Peppol network.

MCP inputs:

Integration options for integration.use:

• "peppol-via-pop" or "peppol" — Submit via POP Peppol
• "pop-to-webhook" — Deliver to a webhook (requires id)

VAT exemption rules specific to Peppol:

• data.nature is the VAT exemption code (a VATEX code such as VATEX-EU-G, VATEX-EU-IC, VATEX-EU-AE or VATEX-EU-O; these are examples, not a complete list). It stays a free string: the POP API verifies it and answers with a plain-language error.
• The exemption code comes from the user. The model never chooses, infers (countries, vies, VAT rate) or changes it, and asks when it is missing. An API error is shown to the user and the call is not retried with another code.
• The API requires data.delivery_data.country (ISO 3166-1 alpha-2, country only, never the address) when the code is VATEX-EU-IC. delivery_data.date (YYYY-MM-DD) is optional and defaults to the document date. A credit note carries the same delivery_data as the invoice it reverses.

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "user_agent": "pop-mcp",
  "user_agent_version": "1.0.0",
  "data": { "...invoice fields...", "nature": "VATEX-EU-IC", "delivery_data": { "country": "FR" } },
  "integration": { "use": "peppol-via-pop", "action": "create" }
}

pop_create_pdf_invoice

Generate a branded PDF invoice. Optionally email it to up to 3 recipients.

MCP inputs:

data.pdf fields:

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "user_agent": "pop-mcp",
  "user_agent_version": "1.0.0",
  "data": {
    "...invoice fields...",
    "pdf": {
      "doc_type_title": "Invoice",
      "logo_url": "https://example.com/logo.png",
      "head": { "store_info_address": "Via Roma 1, 00100 Roma IT", "billing": [] },
      "total_tax": "22.00",
      "email_invoice": { "to": ["[email protected]"] }
    }
  }
}

pop_create_ksef_invoice

Generate a Polish KSeF FA(3) XML invoice or credit note. Optionally submit it through a configured KSeF provider integration.

MCP inputs:

Domain rules specific to KSeF:

• Poland only — transfer_lender.personal_data.tax_id_vat.country_id must be "PL" with a 10-digit NIP as id_code
• customer_type must be "company" or "freelance" (no private individuals)
• nature is always required at the top level for KSeF (unlike SdI/Peppol, where it's only required at 0% VAT) — reuses the same SdI nature codes (N1, N2.1, N2.2, N3.1, N3.2, N4, ...) to derive KSeF's internal fiscal variant
• transmitter_data is not used (SdI-only concept)
• payment_data.payment_details only accepts MP01, MP02/MP03, MP05, MP08 — other payment method codes are rejected at generation time
• Base XML generation is available on any plan; provider submission via integration.use: "ksef" requires a Basic+ plan and the supplier already enrolled as a KSeF legal entity in the POP dashboard

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "user_agent": "pop-mcp",
  "user_agent_version": "1.0.0",
  "data": { "...invoice fields...", "nature": "N1" },
  "integration": { "use": "ksef", "action": "create" }
}

integration is omitted entirely for local XML-only generation (no provider submission).

Returns: raw FA(3) XML (application/xml) for local generation, or JSON (with a UUID) when submitted through a provider integration.

pop_create_zugferd_invoice

Generate a ZUGFeRD/Factur-X document package: a visual PDF, an EN16931 CII XML, and a hybrid PDF/A-3 with the XML embedded.

MCP inputs:

This tool has no integration parameter — ZUGFeRD generation is local only, with no submit/delivery step.

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "user_agent": "pop-mcp",
  "user_agent_version": "1.0.0",
  "data": { "...invoice fields..." }
}

Returns: JSON with generation metadata and three Base64-encoded attachments:

{
  "success": true,
  "data": {
    "valid": true,
    "profile": "EN16931",
    "attachments": {
      "pdf": { "filename": "...", "mime": "application/pdf", "content_base64": "..." },
      "xml": { "filename": "...", "mime": "application/xml", "content_base64": "..." },
      "hybrid_pdf": { "filename": "...", "mime": "application/pdf", "content_base64": "..." }
    },
    "validation": { "...": "..." },
    "errors": [],
    "warnings": []
  }
}

pop_get_invoice_status

Retrieve the SdI processing status and notifications for a submitted invoice.

MCP inputs:

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "integration": { "uuid": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" }
}

SdI notification statuses: pending · accepted · rejected · delivery

SdI processing is asynchronous and can take minutes to hours. Retry if no notifications are returned yet.

pop_get_peppol_document

Retrieve a Peppol document from the network by UUID.

MCP inputs:

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "integration": { "uuid": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx", "zone": "IT" }
}

zone is omitted from the payload if not provided.

pop_get_sdi_document

Retrieve an archived SdI (FatturaPA) document from POP storage by UUID.

MCP inputs:

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "integration": { "uuid": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" }
}

Requires: Basic+ plan with active SdI integration.

pop_verify_sdi_document

Validate an SdI XML document for compliance before submission. Does not submit the document.

MCP inputs:

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "skip_business_check": true,
  "integration": { "xml": "<base64-encoded-xml-string>" }
}

Validation checks performed: XML schema conformance · fiscal code format · VAT number validity · required field presence · amount consistency

Requires: Basic+ plan with active SdI integration and registered business.

pop_preserve_document

Archive an SdI document in certified long-term digital storage (conservazione sostitutiva). Italian law requires invoices to be preserved for 10 years.

MCP inputs:

API payload sent:

{
  "license_key": "YOUR_LICENSE_KEY",
  "integration": { "uuid": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" }
}

Important: Only call this tool when pop_get_invoice_status returns status RC (Ricevuta di Consegna) or MC (Mancata Consegna). Do not call for statuses NS, EC, SE, or DT.

Requires: Basic+ plan with active SdI integration.

Usage Examples

Generate a Simple Italian Invoice (XML Only)

Ask your AI assistant:

"Create a FatturaPA invoice for 1000€ + 22% VAT to Rossi SRL (VAT IT12345678901, Milan). My company is Bianchi SRL (VAT IT98765432109, Rome), using payment method bank transfer to IBAN IT60X0542811101000000123456."

Submit Invoice to SdI

"Create and submit to SdI an invoice #45 for consulting services, 500€ + 22% VAT to customer Mario Rossi (fiscal code RSSMRA80A01H501U) in Rome."

Check Invoice Status After Submission

"What's the status of SdI invoice with UUID abc123-def456-...?"

Generate PDF with Email Delivery

"Create a PDF invoice for order #123 and email it to [email protected]."

Verify SdI Document Before Sending

"Verify SdI document with UUID abc123-... for compliance before submission."

Plan Requirements

Testing

MCP Inspector (Interactive)

npm run inspector
# or
npx @modelcontextprotocol/inspector dist/cli.js

Quick Smoke Test

POP_API_KEY=your_key node -e "
import('./dist/cli.js').catch(e => {
  if (e.message.includes('stdin')) process.exit(0);
  console.error(e); process.exit(1);
});
"

Test Tool Schema Listing

echo '{"jsonrpc":"2.0","id":1,"method":"tools/list","params":{}}' | POP_API_KEY=test node dist/cli.js

Development

# Run with auto-reload
npm run dev

# Build
npm run build

# Clean build artifacts
npm run clean

Invoice Data Structure

The data parameter for invoice creation follows the FatturaPA structure:

data
├── id                    Invoice/order ID (numeric)
├── filename              Output filename without extension (e.g. 'IT99900088876_00009')
├── type                  "invoice" | "credit_note"
├── version               "FPR12" | "FPA12"
├── sdi_type              7-char SDI code ('0000000' for private individuals)
├── customer_type         "private" | "company" | "freelance" | "pa"
├── nature                VAT exemption code (required when rate is 0%, e.g. 'N2.1', 'N6.1')
├── transmitter_data
│   ├── transmitter_id    { country_id, id_code }
│   ├── progressive       Transmission progressive ID (e.g. '00001')
│   ├── transmitter_format  "FPR12" | "FPA12"
│   ├── sdi_code          7-char code
│   ├── transmitter_contact { phone, email }
│   └── recipient_pec     PEC email (alternative to sdi_code)
├── transfer_lender       Supplier/seller
│   ├── personal_data     { tax_id_vat: { country_id, id_code, tax_regime }, company_name }
│   ├── place             { address, zip_code, city, province_id, country_id }
│   └── contact           { phone, email }
├── transferee_client     Customer/buyer
│   ├── personal_data     { tax_id_vat, tax_id_code (fiscal code for IT private), company_name }
│   └── place             { address, zip_code, city, province_id, country_id }
├── invoice_body
│   ├── general_data      { doc_type (TD01|TD04), date (YYYY-MM-DD), invoice_number, currency }
│   └── total_document_amount
├── order_items[]
│   ├── description, quantity, unit
│   ├── unit_price, total_price
│   ├── rate              VAT rate as string (e.g. '22.00')
│   ├── total_tax         VAT amount (number)
│   └── item_type         "product" | "shipping" | "fee"
├── payment_data
│   ├── terms_payment     TP01 (instalment) | TP02 (full) | TP03 (advance)
│   ├── payment_details   MP01 (Cash) | MP02 (Check) | MP05 (Bank Transfer) | MP08 (Credit Card) | ...
│   ├── payment_amount
│   ├── beneficiary       Required for MP05 (bank transfer)
│   ├── financial_institution  Required for MP05
│   └── iban              Required for MP05
├── purchase_order_data   (optional) { id, date }
├── delivery_data         (optional, Peppol) { country, date? } — country required for VATEX-EU-IC
├── connected_invoice_data[]  (required for credit notes) { id, date }
├── overrides             (optional) { language, bollo_force_apply }
└── pdf                   (only for pop_create_pdf_invoice)
    ├── doc_type_title
    ├── logo_url
    ├── head              { store_info_address, billing[], shipping[] }
    ├── total_tax
    ├── email_invoice     { to[] (max 3), from }
    └── footer_text

Error Reference

Related Projects

• n8n-nodes-pop — n8n community nodes for POP
• POP — Official website
• API Documentation — Postman docs

License

MIT © getpopapi