a browser extension that renders a cognometric readout next to every response from chatgpt, claude, gemini, and grok. seven fault kinds. three axes. runs entirely in your browser — your chats never leave your machine.
the badge appears underneath every assistant response. hover a fault chip to see the exact reason styxx flagged it.
chrome://extensions, toggle Developer mode on (top right), click Load unpacked, select the unzipped folder.about:debugging#/runtime/this-firefox, click Load Temporary Add-on, select manifest.json inside the unzipped folder.chat.openai.com, claude.ai, gemini.google.com, or grok.com. badges appear automatically next to assistant responses.classifier.js. the extension has no analytics, no backend, no network calls. you can read all 300 lines of it on github.
what it does NOT do: this is the Tier 3 pipeline from the Cognometric Fingerprint Specification v1.0 — text-only features, no logprobs. accuracy is substantially lower than the logprob-based Tier 1/2 pipelines. a confidence_penalty of 0.25 is applied to aggregate trust values.
for production-grade cognitive profiling, run the full styxx.profile Python pipeline via pip install -U styxx. see fathom.darkflobi.com/profile.
| test case | expected | result |
|---|---|---|
| math reasoning (derivation-heavy) | reasoning | pass |
| clean factual retrieval | retrieval | pass |
| obvious confabulation (made-up chemistry) | confab / retrieval + unverified_claims | pass |
| strong refusal | refusal | pass |
| full-agreement sycophancy | sycophant | pass |
| adversarial / jailbreak | adversarial | pass |
| creative narrative | creative | pass |
| hedged low-confidence | reasoning / incoherence | pass |
| edge cases (empty, 3-word, null) | graceful fallback | pass |
test suite: _test_classifier.js in the extension source. run with node _test_classifier.js. all 26 assertions passing on v0.1.0.
styxx scope implements the Cognometric Fingerprint Specification v1.0, the first open reference for measuring AI cognition.
Fathom Lab. Cognometric Fingerprint Specification v1.0. Zenodo, 2026-04-24. DOI: 10.5281/zenodo.19746215. CC-BY-4.0.