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A Blogger Fingerprinted OpenRouter's Anonymous Ox-Alpha as GLM Using Gzip Compression Distance and the Model's Own Confession
Dejan published on 2026-08-23 that feeding ox-alpha's system prompt back as a user message made it break character and say it is GLM, made by Z.ai. He then confirmed it with a parameter-free Normalized Compression Distance test over 60 prompts against GPT-5.5, Claude Opus 5, two Gemini variants and GLM-5.3, where k-NN matched 7 of 14 ox-alpha queries to GLM-5.3, against 3 for Opus 5. Independently, the Rails lemans benchmark scored the same stealth model at 52/63 with 28.6% Rails API recall, so a free preview slot on OpenRouter is currently serving a top-tier open-weight model.
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