Sidenote
Sidenote is an AI-powered browser extension available for Chrome, Edge, and Firefox that transforms how you interact with documents in your browser. Unlike typical AI summarizers that may produce plausible but unverifiable claims, Sidenote ensures every answer is traceable to an exact passage in the source material. By clicking on a citation, the extension scrolls to and highlights the originating text, allowing immediate verification. This approach eliminates the risk of hallucinated content, making it a reliable tool for research, documentation, and knowledge work. The extension works directly within the browser side panel, supporting a wide range of sources including Confluence, Notion, SharePoint, Google Docs, PDFs, Word documents, web pages, arXiv papers, and Slack canvases. Once a document is ingested, users can summarize its content, ask questions via a chat interface, generate explanations, build glossaries, and even search by semantic meaning. Notes and highlights can be anchored to specific passages, and shareable snapshot links allow collaborative verification. All interactions remain within the context of the open document, preserving workflow continuity. Sidenote operates by extracting, chunking, and embedding document text in seconds; subsequent access to the same document is cached to avoid reindexing costs. Users can choose between two retention modes: Store, which keeps the document indexed for the lifetime of the account, or Discard, which purges all data within 24 hours. Embeddings are stored in a UK-based Supabase pgvector database with row-level security to isolate data per account. The extension offers a free tier with a 7-day Pro trial and no credit card required, ensuring accessibility for individual and team use.
- Category
- Chrome Extensions
- Pricing
- Unknown
Problem solved
Sidenote addresses the problem of hallucinating AI summaries and document chat tools that generate plausible-sounding but unverifiable claims. By ensuring every answer cites the exact source passage and allowing instant in-document verification, it provides users with confidence that the information they receive is grounded in the actual material, eliminating the risk of acting on fabricated content.
Use cases
- Summarize long documents or web pages into key points
- Chat with a document to extract specific information
- Verify AI-generated claims by clicking citations to see original text
- Build glossaries of terms defined in a document
- Search across multiple documents in a collection
- Highlight and annotate passages for later reference
- Share cited answers with colleagues via revocable snapshot links
Audience
- Business Users
- Researchers
- Product Managers
- Content Creators
- Developers
Pros
- Every answer includes verifiable citations to the source material
- Works across diverse sources like Confluence, Notion, PDFs, and web pages
- Free tier available with full core features
- Seamless browser integration without leaving the current tab
- Data privacy options with choice of retention policies
Cons
- Limited to browser environments (no mobile or desktop app)
- Requires an internet connection for AI processing
- Cloud-based document processing may raise security concerns for sensitive content
- Processing speed depends on document size and server load
- Some advanced features may require a Pro subscription
Official website: https://getsidenote.app/
Canonical LambdaBase page: https://www.lambdabase.com/tools/sidenote