Show HN: DocMason – Agent Knowledge Base for local complex office files (github.com) AI

DocMason is an open-source, repo-native agent app that builds a local, evidence-first knowledge base from private files (Office documents, PDFs, and emails) so answers are traceable to exact source locations. Instead of flattening documents into unstructured text, it preserves document structure and visual/layout semantics (with local parsing via LibreOffice/PDF tooling) and enforces validation and provenance boundaries. The project is positioned as running entirely within a local folder boundary, with no document upload by DocMason itself, and includes a macOS setup flow and a demo corpus to test traceable “deep research” answers.