Copilot for Supernote: chat with your notes, PDFs, and EPUBs using your own LLM key
Built a Supernote plugin that lets you summarise, explain, or ask questions about whatever's on the current page (handwritten notes, PDFs, or EPUBs) using your own API key for ChatGPT, Claude, Gemini, or DeepSeek. Sharing it with the community here.
No backend. No telemetry. No "free" tier where the device maker silently bills your taps against a shared key. You bring the key, every billable request lands on your provider dashboard, and you can revoke or rotate it at any time.
What it provides
Four one-tap action buttons sit at the top of the chat panel so the common questions are a single tap, no typing:
- ☰ Summary: a structured digest of what's on the current page.
- ? Explain: a longer breakdown for when "summary" isn't enough; useful on textbook-style content.
- ✦ Clarify: flags what's unclear, ambiguous, or needs follow-up. Helpful on lecture notes / first-pass meeting notes.
- ⊡ Snapshot: a compact set of bullets you can copy back into your note as a "table of contents" for the page.
Plus:
- Free-form chat about the visible page in the same overlay (type at the bottom, hit send).
- Markdown-rendered replies with a one-tap **Copy** so you can paste the answer back into a note.
- Works on the current page only. Each request captures the page screenshot (vision-capable providers) plus extracted text (PDF text layer or handwriting OCR).
Why this is different
Most AI features on e-ink readers ship with a vendor-supplied key behind the scenes. Convenient, but you can't see the bill, you can't audit what's sent, you can't switch providers, and your data is on someone else's hands. Here the trade is reversed:
- You own the key. It lives in a text file on your device. Never uploaded.
- You own the chats. Requests go directly from your device to the provider you chose. We never see them.
- You own the audit. Every request shows up on your OpenAI / Anthropic / Google / DeepSeek dashboard: billable, dated, attributable.
Providers + default models in the templates
| Provider | Default Model | Vision (Page Image) |
|---|---|---|
| OpenAI (ChatGPT) | gpt-4o-mini | Yes |
| Anthropic (Claude) | claude-haiku-4.5 | Yes |
| Google Gemini | gemini-2.5-flash | Yes |
| Deepseek | deepseek-chat | text only (no vision endpoint) |
Approximate cost per page summary on the cheapest models is well under a US cent. A heavy day is still under $0.10 across any of them.
Demo
Quick start
- Grab an API key from your provider's console.
- On the Supernote, create the folder `MyStyle/SnCopilot/` (USB sync, WebDAV, or Cloud, whatever you already use).
- Save a file `copilot-key-<provider>.txt` in that folder with three lines:
- >Example: copilot-key-openai.txt would have something like this
- ```
- provider=openai
- model=gpt-4o-mini
- key=sk-proj-1345abCDef67890...
- ```
- Tap the brain icon from the plugins menu of any note, PDF, or EPUB.
That's it. Templates for all four providers ship in the repo's `templates/` directory.
If you want to use multiple providers
Drop more than one `copilot-key-<provider>.txt` and add `default_provider=<provider>` to one of them (it doesn't have to be the file you're naming; any of them can declare the default). Example for an Anthropic key file when both OpenAI and Anthropic are configured:
```
provider=anthropic
model=claude-haiku-4-5
key=sk-ant-...
default_provider=openai
```
Without a default, the plugin shows a "pick one" message in Settings and refuses to send. With conflicting `default_provider=` values across files, same thing.
UPDATE
Security Focused Release v1.0.2
Privacy posture
The page screenshot and any transcribed text are sent to the LLM provider you configured. There's no on-device redaction toggle that would create a false sense of safety while shipping the same content via the image. Be deliberate about which page is open before tapping Copilot. On DeepSeek (text-only) the plugin silently scrubs emails and 7+ digit runs, since that's the one path where redaction actually reduces what we ship.
Repo / release
- Source : https://github.com/j-raghavan/sn-copilot
- Release: https://github.com/j-raghavan/sn-copilot/releases/tag/v1.0.1
Feedback and issue reports welcome.