The Pdf Annotator plugin allows users to annotate PDFs directly within Obsidian. Features include text highlighting, comments, stamps, shapes such as circles and rectangles, and signature addition. While the plugin currently saves annotations within the Obsidian vault, it does not embed them into the PDF file itself due to the limitations of the pdf.js version supported by Obsidian. The annotations follow the pdf.js extension format, ensuring potential future compatibility for saving directly into PDF files. This tool is ideal for users who need robust PDF annotation capabilities integrated with their Obsidian workflow.