The opposite of "idem".
Notidem is an open-source Chrome extension that helps you write genuine, on-brand LinkedIn comments and message replies with AI — in your own voice, always reviewed by you before anything is posted.
Most people reply with "idem", "great post!", or "totally agree". Those replies cost nothing and mean nothing. Notidem helps you do the opposite: thoughtful, specific replies that actually build relationships, drawn from your own profile and the context in front of you.
Notidem is a drafting assistant, not an automation tool. It never posts, sends, or acts on your behalf. You read every draft, edit it, and send it yourself.
2-minute walkthrough — from install to first reply.
- Comments on the feed. Open any post, click the Notidem button by the comment box, pick a goal (add an insight, share an experience, ask a question, agree and build on it, or offer a respectful counter-point), and get a draft grounded in the post and in your profile.
- Message replies. In a conversation thread, Notidem reads the visible history and helps you write a reply that fits the context — reply naturally, thank, propose a next step, answer a question, or politely decline.
- Your voice, your context. You add a short profile and, optionally, your résumé. Notidem uses it as quiet context for tone and credibility — it never pastes your résumé back into a comment.
- Bring your own key. Use your own API key from OpenAI, Anthropic, Gemini, or Groq. Your key is encrypted on your device and sent only to the provider you choose.
Security is a first-class concern, and we are honest about what is and isn't possible in a browser extension.
- The API key never touches the LinkedIn page. All network calls and key handling happen in the extension's isolated background worker. No page script — LinkedIn's or anyone else's — can read your key.
- Encrypted at rest. Your key is encrypted with AES-GCM (Web Crypto API) before being stored.
- Local only. Keys live in
chrome.storage.localand are never synced to the cloud. - Never logged. The key is never written to the console or any log.
- Sent only to your chosen provider. No Notidem server sits between you and the AI. We never see your key, your text, or your drafts.
- You can wipe it anytime with "Forget my keys" or "Clear all data".
Honest limitation: no browser extension can fully protect a key against malware already running on your computer — to use a key, it must be decrypted in the browser. For maximum safety, use a scoped key with a low spend limit and remove it when you're done.
See the end-to-end data flow:
Full details: docs/PRIVACY.md · docs/SECURITY.md · docs/PERMISSIONS.md
- LinkedIn. Notidem keeps a human in the loop at all times. It reads only what is already visible on your screen, drafts text you must review, and never auto-posts, auto-sends, mass-messages, scrapes in bulk, or automates any action. This is deliberately the opposite of the templated, mass-outreach pattern LinkedIn's systems flag.
- LGPD / GDPR. Notidem processes personal data (the text you choose to send to an AI provider) locally and transiently, under your control, for the sole purpose of drafting your reply. There is no Notidem backend collecting or storing this data. The lawful basis is your own consent, exercised each time you click Generate. You may erase all locally stored data at any time. See
docs/PRIVACY.md.
Notidem is an assistant, not a bot. LinkedIn's terms prohibit automation, bulk scraping, and mass outreach — and so does Notidem, by design.
- You are always in the loop. Notidem only drafts. You read, edit, and send every message and comment yourself. There is no auto-post, no auto-send, no queue, and no "reply to all".
- It reads only what is already on your screen, and only when you click Generate. It does not crawl profiles, harvest connections, or collect anyone else's data.
- No rate-limit evasion. Notidem does not simulate typing, randomize timing, or take any action designed to disguise automated behavior, because it performs no automated behavior.
- Use it at a human pace. Treat it like a writing aid (a spell-checker or a "rewrite" helper), not a growth tool. Quality replies, not volume.
- "For LinkedIn", not "from LinkedIn". Notidem is an independent, unofficial tool. It is not affiliated with, endorsed by, or connected to LinkedIn, and does not use LinkedIn's trademarks to imply otherwise.
Notidem is not affiliated with LinkedIn. "LinkedIn" is a trademark of its respective owner. Use of any third-party platform is subject to that platform's own terms; you are responsible for your own use. This project is provided as-is, without warranty (see LICENSE).
Notidem is pending review on the Chrome Web Store. Until then, you can install the packaged build directly:
- Download the latest
notidem-vX.Y.Z.zipfrom Releases. - Unzip it.
- Open
chrome://extensionsin Chrome. - Turn on Developer mode (top-right).
- Click Load unpacked and select the unzipped folder.
- Open the extension's Settings, add your AI provider key, and write a short profile.
- Go to LinkedIn, open a post or a conversation, and click the Notidem button.
A friendlier install page lives at the project site (GitHub Pages) — see docs/.
- A content script detects the comment box or message composer by its stable structure (not by a single fragile class name), and adds a Notidem button.
- When you click Generate, it reads the visible post text or conversation transcript.
- It sends that text to the background worker, which builds a prompt using your profile and the goal you picked.
- The background worker calls your chosen AI provider directly over HTTPS.
- The draft comes back. You review it, edit it, and insert it. Nothing is posted automatically.
The insert step uses a synthetic paste event so the text is routed through LinkedIn's own editor model (Quill) — it never writes to the DOM directly, which would corrupt the editor.
- Per-context profiles — different voices for when you're a candidate, a recruiter, in sales, or networking, mirroring how people actually use LinkedIn.
- Optional hosted AI — for people who don't want to manage an API key, an opt-in credits model where the key lives on a server and never in the browser. The bring-your-own-key path stays free and open forever.
- More languages and tone presets.
See docs/ROADMAP.md.
Manifest V3, vanilla JavaScript (no build step), Web Crypto API for at-rest encryption, strict Content Security Policy, and a minimal permission set (storage plus the four AI provider hosts). The full source is here for you to audit.
Issues and pull requests are welcome. If you find a security concern, please read docs/SECURITY.md first.
MIT — see LICENSE.