Credibility Analyzer by Evergreen-Labs.org

Credibility Analyzer helps you quickly judge whether a webpage (or selected text) is reliable.

Analyze the full page from the toolbar, or highlight text and use the right-click menu. You’ll get:
• A credibility / factualness score from 1–10
• A short justification of the score
• A clear bullet-point summary (3, 4, or 5 points — configurable)
• Results in the same language as the page when possible

AI models (bring your own API key)
• Gemini Flash (latest) — Google’s current Flash model with live web grounding for fact-checking
• Claude Sonnet — Anthropic’s Sonnet for knowledge-based analysis
• GPT-5.6 — OpenAI’s GPT-5.6 for knowledge-based analysis

How to use
1. Open Settings and add an API key for at least one provider
2. Visit a normal webpage
3. Click the Credibility Analyzer toolbar icon (or right-click selected text → Analyze credibility)
4. Choose a model and click Go
5. Review the summary and credibility score

Privacy
• Analysis runs only when you start it
• Page content (and optionally the URL, if you enable “Include URL context”) is sent to the AI provider you selected, using your API key
• The extension author does not run a backend that stores your page content
• API keys stay in your Firefox extension storage
• No ads, no analytics SDK, no account required from us

Requirements
• Firefox 140 or later
• An API key from Google AI Studio, Anthropic, and/or OpenAI for the models you want to use

Notes
• Restricted Firefox pages (about:, Mozilla pages, etc.) cannot be analyzed
• Cloud AI usage is billed by the provider under your account with them

Make complex articles easier to skim — and easier to trust or question — without leaving Firefox.