AbdullahAlhariri / penmentor

A maths mentor at the tip of your pen. Press a key while you work by hand: Claude, Gemini or GPT marks your work on the 
screen like a teacher with coloured pens, gives you hints instead of answers, and shows the idea as a 3Blue1Brown-style animation.
 Handwriting in xournal++ → one key → the slip is marked on the page → box the integral → an interactive manim animation.
( video ; for a repeatable recording the pen is scripted and the model's answer is a fixed example.) 
## Why I use it
I study calculus with a pen tablet in xournal++. I kept screenshotting my work into Claude and reading long answers
back, when what I wanted was a teacher looking over my shoulder: circle the mistake, tick what's right, nudge me toward
the next step, and *show* me why. penmentor is that, one key away, on my own Claude subscription.
## How it helps you learn
- **Hints, not answers.** A ladder from a nudge to naming the technique to a faint ghost of the next line: you do
 the thinking, which is what makes it stick.
- **Feedback on your own work.** The first real mistake circled where you made it, correct lines ticked, later lines
 that inherit the mistake underlined. The marks stay while you keep writing; Esc clears them.
- **Practice that makes you recall.** Questions on your key steps (answer by typing or by writing), find-the-error
 drills, "which technique fits?".
- **See it.** Box what you want to understand and get an interactive animation made with 3Blue1Brown's own
 manim: drag the bounds, retype a value, watch Riemann sums close in.
- **Whole page aware.** A small xournal++ plugin shares the page you are on, not just what fits on screen.
## Works with Claude Code, Codex and Antigravity
penmentor runs on the AI command-line agent you already use, on that subscription. Pick the model in *Settings*; its
prefix says which agent answers:
| Prefix | Agent | For example |
|---|---|---|
| `claude:` | Claude Code | `claude:opus`, `claude:sonnet`, `claude:haiku` |
| `codex:` | Codex | `codex:gpt-5.6-terra` |
| `agy:` | Antigravity CLI | `agy:gemini-4-argon-medium`, `agy:gemini-3.8-flash-medium` |
Settings lists the agents you have installed. How each one is run and what it sees: the guide.
## Quick start
 [code] 
Linux on X11 (best with i3), with one of those agents logged in (`claude`, `codex` or `agy`), plus `rofi`, `slop`,
`xdotool` and PyQt6. Bind `bin/penmentor` to a key (example). Setup, keys and how it works: the guide.
## License
MIT