Harper groups the patterns hiding in your own writing. Pick a model here to turn those short crumbs into a lesson, not a generic grammar course.
9 mistake categories0–3 mastery levelsBuilt in your browser
Harper groups the mistakes. Pick a model here to build the quiz from those short lines.
Lesson model
Detected weakness clusters
VerbaClara analyzes your typing history across the web to pinpoint your recurring blind spots.
Settings
Shape how VerbaClara reads.
Choose the brain, the language it explains in, and how much checking happens while you write. Harper is the default and stays on this computer.
Configure AI model, languages, and auto-checking.
Plan
Free. Grammar uses Harper on this computer. Nothing is uploaded.
A local model or your own API key is optional, for rewriting and lessons.
VerbaClara does not run a server that reads your mail.
Online APIs run only when you choose OpenAI or Google and press a fix.
How VerbaClara checks
Practice lessons
Harper files each catch into a learning category, such as Articles or Prepositions.
Starting a lesson sends only those short wrong → correct lines to the model below. The email stays on this computer.
Languages
Offline explanations: Spanish, Portuguese, German, French, Italian, Japanese and Croatian. Other languages need a model; English is the offline fallback.
Privacy
Harper and a local model keep the sentence on this computer.
OpenAI and Google see the sentence only when that mode is selected.
Emails, phone numbers, URLs, and long numbers are masked before any cloud call.
History stores only short grammar crumbs (wrong → correct + rule), never full emails.
Auto mode
Off by default. Triggers when you stop typing for a moment and checks only what you
just typed — never old text that was already on the page.
When a fix is found, a small suggestion badge appears next to the sentence — it does not cover what you are writing.
Click the badge to open the card, or press Alt+G for the explanation. Alt+A applies, and Alt+I ignores. Continue typing to dismiss it; nothing appears when there is nothing to fix.
With Harper this stays on your computer and does not use an API.
A local model or an online API uses that engine on each pause.
My mistakes history
No corrections yet. Select some text on any page and click the VerbaClara button!
Only short grammar fragments (up to 80 characters per side) are stored in this browser. Full messages and documents are not saved.