pdf-filler-mcp

An MCP server that lets Claude fill any PDF form — scanned or AcroForm — through a browser-based drag-and-drop editor.

Editor — drag, reposition and edit fields directly on the rendered PDF page:

Result — the generated PDF with all fields overlaid:

How it works

1. Claude renders the PDF to images and inspects the layout

2. Claude places markers on each field and iterates until placement is correct

3. Claude opens the editor — a self-contained HTML page where you drag fields, edit values and click Fertig

4. PDF is generated automatically — the editor POSTs to a local receiver which runs headless Playwright to produce the final PDF

The entire stack runs locally. No data leaves your machine.

Related MCP server: JustFill PDF Forms

Tools exposed

Prerequisites

• Python 3.9+

• pymupdf (pip install pymupdf)

• pypdf (pip install pypdf) — for merging

• Node.js + Playwright — for the auto-PDF-generation step (npm i -g playwright)

Installation

1. Clone

git clone https://github.com/patroqueeet/pdf-filler-mcp.git ~/.claude/pdf-filler

2. Register with Claude Code

Add to ~/.mcp.json:

{
  "mcpServers": {
    "pdf-filler": {
      "command": "python3",
      "args": ["~/.claude/pdf-filler/filler.py", "serve"]
    }
  }
}

Restart Claude Code — the pdf_* tools will be available in any session.

Typical workflow

User: Fill out /tmp/application.pdf with my personal data

Claude:
  1. pdf_render       → get page images + scale_factor
  2. pdf_preview      → place marker dots, read result image, adjust
  3. pdf_memory_get   → check if layout is already saved
  4. pdf_receiver_start → start PDF receiver on port 7789
  5. pdf_editor_multi → open editor in browser
  6. pdf_receiver_wait → wait for user to click Fertig
  → returns: { done: true, output_path: "/tmp/application_filled.pdf" }

Editor features

• Click to create a field anywhere on the document image

• Drag the ⣿ handle to reposition

• Tab between fields; inline editing

• Checkbox type available via the ➕ button

• Multi-page navigation with per-page field state

• Print CSS hides all editor chrome — only text overlays are printed

Running the tests

pip install pymupdf pypdf pytest pytest-timeout
pytest tests/ -v

License

MIT — see LICENSE.