polydoc-mcp
An MCP server for PolyDoc, a REST API that converts HTML or URLs to PDF, captures screenshots, and generates EU-compliant e-invoices (Factur-X / ZUGFeRD hybrid PDF/A-3). It lets MCP clients (Claude Desktop, Claude Code, Cursor, and others) drive PolyDoc directly.
polydoc_html_to_pdf - HTML, URL, or saved template to PDF (layout, margins, page format, page ranges, bookmarks, accessible/tagged PDFs).
polydoc_screenshot - HTML, URL, or template to PNG / JPEG / WebP, with viewport and device-pixel-ratio control. Returns an inline image preview when small enough.
polydoc_generate_einvoice - Factur-X or ZUGFeRD hybrid PDF/A-3 from structured invoice data, profiles from minimum to extended.
polydoc_test_credentials - verify the configured API key with a minimal sandbox render (never draws production quota).
Content can come from a URL, an inline HTML string, or a saved template (with Liquid templateData). Downloads are written to a local directory and the file path is returned; you can also deliver to your cloud storage (presigned URL) or a webhook.
Installation
Requires Node.js >= 20.15. Published to npm, so clients can run it with npx:
The server is configured entirely through environment variables (see below).
Configuration
| Variable | Required | Default | Description |
|---|
POLYDOC_API_KEY | yes | - | API key from dashboard.polydoc.tech. |
POLYDOC_SANDBOX | no | false | Default sandbox mode (watermarked, rate-limited). A tool call can override per request. |
POLYDOC_BASE_URL | no | https://api.polydoc.tech | Override for self-hosted or staging. |
POLYDOC_OUTPUT_DIR | no | OS temp dir + /polydoc | Where downloads are written. Output never escapes this folder. |
Client setup
Claude Desktop
Add to claude_desktop_config.json (Settings > Developer > Edit Config):
{
"mcpServers": {
"polydoc": {
"command": "npx",
"args": ["-y", "polydoc-mcp"],
"env": {
"POLYDOC_API_KEY": "your-key",
"POLYDOC_OUTPUT_DIR": "/Users/you/Documents/polydoc"
}
}
}
}
Claude Code
claude mcp add polydoc -e POLYDOC_API_KEY=your-key -- npx -y polydoc-mcp
Cursor
Add to ~/.cursor/mcp.json (or a project .cursor/mcp.json) using the same mcpServers block shown for Claude Desktop.
Output and delivery
- Download (default): the file is written under
POLYDOC_OUTPUT_DIR and the absolute path is returned with metadata (size, conversion id, credits). Screenshots also return an inline image block. Pass returnBase64: true to also receive the bytes as base64 (heavy; for clients without a filesystem).
- Cloud storage: set
delivery: "cloudStorage" and presignedUrl. The upload URL is returned.
- Webhook: set
delivery: "webhook" and a webhook object ({ url, async?, method?, headers? }).
Every conversion tool has an advanced object that is deep-merged into the request body, so any API capability not surfaced as a typed field (for example pdf.watermark, pdf.encryption, render, request) is still reachable. See the field reference at docs.polydoc.tech.
Examples
Worked tool inputs for each angle live in examples/: a branded PDF from a template, a URL screenshot, and a ZUGFeRD / EN 16931 e-invoice.
Development
yarn install
yarn build - compile to dist/
yarn lint
yarn test - unit tests (request builder, output jail, tool handlers) and an in-memory MCP round-trip
POLYDOC_API_KEY=your-key yarn test:integration - live smoke tests against the sandbox
yarn scrub:check - check for em-dashes in source and docs
Run the built server directly for a quick check:
POLYDOC_API_KEY=your-key node dist/index.js
License
MIT