CastPDF

Name: CastPDF
Author: castpdf

@castpdfMCP server · External

Create PDFs from your CastPDF templates or HTML, issue EU e-invoices, and look up documents.

PDF toolsv0.1.0MITTypeScript

Freeno charge per call

How to install

Runs on your machine from its package; the steps are below.

What it does

Reads
Writes
High impact

At most: creates or changes data: records, files, settings.

What it costs

Free

Odel charges nothing per call. The publisher may charge for its own service.

Runs locally over stdio

This server isn't hosted — your MCP client launches it from a package registry. Use one of the commands below, or drop the config into your client (e.g. Claude Desktop).

npm@castpdf/mcpv0.1.0

Run

npx -y @castpdf/mcp

MCP client config

{
  "mcpServers": {
    "castpdf": {
      "command": "npx",
      "args": [
        "-y",
        "@castpdf/mcp"
      ]
    }
  }
}

README4 min readView on GitHub

CastPDF MCP server

The official Model Context Protocol server for CastPDF. It lets AI agents (Claude, Cursor and other MCP clients) list your PDF templates, create PDFs and EU e-invoices, and look up documents, using your CastPDF API key.

Documents are test documents by default (watermarked, not counted against your plan). The agent only makes a live document when you explicitly ask for one, and a cpdf_test_... key can never make live documents at all. Start with a test key.

Tools

Tool	What it does
`list_templates`	Lists your saved templates (id, name, version).
`get_template_fields`	The data a template expects, read from its sample data (fields and line items).
`create_pdf`	Renders a template with `data`, or raw `html`, and returns a signed download URL. `test` defaults to true.
`create_e_invoice`	Issues a ZUGFeRD / Factur-X PDF or an XRechnung XML from a structured invoice and returns a download URL. `test` defaults to true.
`list_documents`	Recent documents, newest first, with status and download URLs.
`get_document`	One document by id: status, error code, fresh download URL.

Download links are signed and expire (see expires_at); the agent shares the link, the file itself is not sent through the conversation.

Setup

You need Node.js 20 or newer and a CastPDF API key (dashboard > API keys). The server reads the key from the CASTPDF_API_KEY environment variable.

Claude Desktop

Settings > Developer > Edit Config, then add to claude_desktop_config.json:

json

{
  "mcpServers": {
    "castpdf": {
      "command": "npx",
      "args": ["-y", "@castpdf/mcp"],
      "env": { "CASTPDF_API_KEY": "cpdf_test_..." }
    }
  }
}

Restart Claude Desktop. On Windows, if npx is not found, use "command": "cmd" and "args": ["/c", "npx", "-y", "@castpdf/mcp"].

Claude Code

claude mcp add castpdf --env CASTPDF_API_KEY=cpdf_test_... -- npx -y @castpdf/mcp

Add --scope user to use it in every project. Check it with claude mcp list or /mcp inside Claude Code.

Cursor

Add to ~/.cursor/mcp.json (all projects) or .cursor/mcp.json (one project):

json

{
  "mcpServers": {
    "castpdf": {
      "command": "npx",
      "args": ["-y", "@castpdf/mcp"],
      "env": { "CASTPDF_API_KEY": "cpdf_test_..." }
    }
  }
}

Do not commit a file that contains your key.

Other clients

Any MCP client that starts stdio servers works with the command npx -y @castpdf/mcp and the environment variable CASTPDF_API_KEY.

Streamable HTTP

For clients that connect over HTTP, or to run one shared server:

CASTPDF_API_KEY=cpdf_test_... npx -y @castpdf/mcp --http --port 3000
# MCP endpoint: http://127.0.0.1:3000/mcp   health check: http://127.0.0.1:3000/health

Every request to that endpoint uses the server's API key, so:

By default it listens on 127.0.0.1 only and accepts only localhost, 127.0.0.1 and [::1] as Host header (DNS rebinding protection) and no browser Origin.
Set CASTPDF_MCP_AUTH_TOKEN to require Authorization: Bearer <token> on every request. It is required to listen on any other interface (--host 0.0.0.0). Put a TLS-terminating proxy in front of it, and list the public host name in CASTPDF_MCP_ALLOWED_HOSTS.
The server is stateless (no sessions, POST only), so it can run behind a load balancer.

Example client config for HTTP (Claude Code):

claude mcp add --transport http castpdf http://127.0.0.1:3000/mcp

Configuration

Variable / flag	Default	Meaning
`CASTPDF_API_KEY`	(required)	Your CastPDF API key.
`CASTPDF_BASE_URL`	`https://api.castpdf.com`	API base URL.
`--http` or `MCP_TRANSPORT=http`	stdio	Serve Streamable HTTP instead of stdio.
`--port` or `PORT`	`3000`	HTTP port.
`--host` or `HOST`	`127.0.0.1`	HTTP interface.
`CASTPDF_MCP_AUTH_TOKEN`	none	Bearer token required on HTTP requests.
`CASTPDF_MCP_ALLOWED_HOSTS`	localhost names	Comma-separated Host header values to accept.
`CASTPDF_MCP_ALLOWED_ORIGINS`	none	Comma-separated browser origins to accept.

Example prompts

"Which CastPDF templates do I have?"
"Make a test PDF of the Invoice template for Ada Lovelace, 3 hours of consulting at 120 EUR."
"Create a ZUGFeRD invoice from Muster GmbH (DE123456789, Berlin) to Kunde AG, Hamburg: 8 hours consulting at 95 EUR, 19 % VAT, payable within 14 days to IBAN DE02 1203 0000 0000 2020 51."
"Did my last document fail? Why?"

Use as a library

import { createServer } from '@castpdf/mcp';
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';

const server = createServer({ apiKey: process.env.CASTPDF_API_KEY! });
await server.connect(new StdioServerTransport());

Version history

0.1.0: first release.

License

MIT

Similar modules

Browse PDF tools