Sidenote vs HARPA AI
HARPA AI is an agent that acts on the web for you; Sidenote is a reader that answers about the document you have open, with every claim pinned to the source passage.
A citation-first reader that grounds every answer in the document you already have open.
An agent that acts: form-filling, scraping, monitoring and multi-model chat across the web.
Should you use Sidenote or HARPA AI?
Choose Sidenote if…
You are reading documents you need to trust (PDFs, wikis, articles) and you want every answer cited to a passage you can click through to and verify.
Choose HARPA AI if…
You want one extension to automate the web (fill forms, scrape and monitor pages, track prices, draft emails) and to pick between many AI models while you do it.
Plenty of people run both: HARPA AI to automate and act across the web, Sidenote when they need a cited, trustworthy read of a specific document.
Sidenote vs HARPA AI: feature by feature.
| Capability | Sidenote | HARPA AI |
|---|---|---|
| Reads the page or document you already have open | Yes | Yes |
| Citations scroll & highlight the exact passage | Yes | No |
| Server-side citation check drops unsupported claims | Yes | No |
| Works on private Confluence, Notion & SharePoint pages | Yes | Partial |
| Ask across many documents at once | Yes | No |
| One-click glossary of jargon & acronyms | Yes | No |
| Reads scanned PDFs with built-in OCR | Yes | Partial |
| Per-document Store / Discard retention control | Yes | No |
| Summarize a document | Yes | Yes |
| Searches the public web | No | Yes |
| Automates web tasks, scraping & site monitoring | No | Yes |
| Choice of multiple AI models | No | Yes |
Last reviewed: 3 July 2026.
HARPA AI wins on reach and action: it searches the live web, automates and monitors pages, and lets you pick between models. Sidenote wins on trust: retrieval across the documents you open, a citation on every claim, and a click that scrolls the live page to the source. The cross-document row is powered by Sidenote Collections.
An agent that acts across the web, or a reader that grounds every answer.
HARPA AI is a browser-automation Swiss-army knife: it combines ChatGPT, Claude, Gemini, Perplexity, DeepSeek and Llama (via web sessions, your own API keys, or its CloudGPT service) with web search, form-filling, scraping, price and site monitoring, email drafting and Zapier, Make and n8n hooks. If you want one extension to do things across the whole web, it is a genuinely broad pick.
Sidenote does one thing and goes deep: it turns the documents you read into something you can question and trust. Every answer is checked server-side against the source, unsupported claims lose their citation, and each citation scrolls the live page to the exact sentence.
Ask “what does this contract say about termination?” HARPA AI gives a capable summary from the page and can search the web around it. Sidenote retrieves the clause, validates the answer against it, drops anything it cannot ground, and scrolls you to the exact sentence to confirm.
Where HARPA AI is the better tool.
HARPA AI is a strong tool that does far more than read. Where these are what you need, it is built for it in ways Sidenote deliberately is not:
Real browser automation
Fill forms, scrape and extract data, monitor sites and track prices, then push results to Zapier, Make or n8n. Sidenote reads and cites; it does not act on the web for you.
Many models, plus the live web
Switch between ChatGPT, Claude, Gemini, Perplexity, DeepSeek and Llama, or connect your own API keys, with web-search-grounded answers. Sidenote picks one model for the job rather than offering a marketplace.
A developer API and custom agents
HARPA exposes a CloudAI API and lets you build reusable custom agents and prompt commands: an automation surface Sidenote does not offer.
Sidenote vs HARPA AI: common questions
Read anything. With citations.
Add Sidenote to your browser, open a document, and ask. Every answer comes with the passage that proves it.
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