Home ↗

Fact-check any AI, right in your browser.

Highlight an answer from ChatGPT, Claude, Gemini — or anything on any page — and get an instant grounded verdict: a hallucination-risk score plus the exact claims the model got wrong. The accuracy layer, wherever you already work.

Download the extension (.zip)

Chrome, Edge, Brave & other Chromium browsers · Chrome Web Store listing coming soon

Right-click

Select text → Verify with Mephistopheles → a verdict card appears on the page.

Toolbar icon

Click the ▲ icon — it prefills with your selection, or paste anything to check.

Install it (two minutes)

  1. Download & unzip the file above. You'll get a mephistopheles-extension folder.
  2. Open chrome://extensions (or edge://extensions) and turn on Developer mode, top-right.
  3. Click Load unpacked and choose the unzipped folder.
  4. Pin the ▲ icon from the puzzle-piece menu — you're done.

Verification runs on this site's public checker. Nothing is stored; the text you verify is sent only to Mephistopheles to be checked against live sources. Not legal or medical advice — "unverifiable" means no source was found, not that a claim is false. ← back to home