klarpdf

An offline PDF engine you can use yourself or hand to an agent: a native Windows viewer + page editor — split, splice, annotate, fill forms, sign with an image, redact — plus a cross-platform 19-tool MCP server for filling, annotating, and redacting PDFs with any MCP-compatible client. No telemetry, no network. PySide6 · PyMuPDF. AGPL-3.0-or-later.

GitHub

Official source

Start locally with the CLI guide