BraiNOTES：浏览器中的PDF手写笔记工具

一位开发者在Hacker News上分享了BraiNOTES，这是一款在浏览器中运行的手写笔记应用，允许用户直接在PDF讲义上进行手写标注。1该工具采用本地优先架构，完全无需账户和后端服务器支持，可以离线使用。1

BraiNOTES作为静态网站运行，使用IndexedDB进行本地数据存储。1应用支持笔压感应功能，并内置手抖滤波算法以提升书写体验。1用户可将笔记导出为.brainotes文件，该格式采用ZIP压缩包结构，包含JSON数据和PDF文档。1应用提供Study模式和Board模式两种工作界面供用户选择。1该项目已在GitHub上开源，采用MIT许可证。1

开发者已与几位朋友在实际使用中测试该工具。1此外，开发者正在开发MCP服务器功能。1

A developer has introduced BraiNOTES on Hacker News, a note-taking application that operates entirely within the browser, enabling users to write handwritten notes directly on PDF lecture documents 1. The tool is built as a static website with no backend server required, utilizing a local-first architecture that eliminates the need for user accounts or external services 1.

BraiNOTES stores all data locally using IndexedDB, allowing for offline functionality and complete user privacy 1. The application supports pressure-sensitive input and includes a hand tremor filter to improve writing quality 1. Users can export their work as .brainotes files, which are ZIP archives containing both JSON data and PDF documents 1. The tool offers two operational modes—Study mode and Board mode—to accommodate different note-taking workflows 1.

The project is available on GitHub under the MIT license and has been actively tested by the developer and several colleagues in real lecture settings 1. The developer is currently working on implementing MCP server functionality as an ongoing enhancement 1.