Theia checks ChatGPT, Claude, and Gemini while you use them, catching hallucinations, sycophancy, and claims that don't hold up, and backing every verdict with real sources.
The reply hallucinates that the Eiffel tower is 200 meters tall, while in reality, it is 330 meters tall.
The tower is 330 m tall, about the height of an 81-story building.
Grounded checks against primary sources, plus an on device sycophancy checker for your convenience.
A gauge sits beside every chat and scores, in real time, how much the model is flattering you versus telling you the truth, powered with a custom trained model.
Highlight a claim or evaluate a whole reply. Theia returns a verdict and confidence.
Run Gemini Nano locally on your own device and verify claims with live web search plus free public sources like Wikipedia, Wikidata, PubMed, OpenAlex, Crossref, SEC EDGAR and more.
Free & unlimitedAdd Theia to Chrome and open any AI chat. The meter appears automatically.
Theia reads the assistant's replies and scores them.
Highlight text or click "Evaluate LLM Message" for a full, sourced fact-check in seconds.
On-device mode runs a local Gemini Nano model and checks claims against live web search and free public sources, so you can verify without limits or a subscription. Faster cloud models are available too, with a free tier.
Add Theia to Chrome and get a second opinion on every answer, always grounded with sources.