Prompt injection and gzip-NCD compression analysis reveal that OX Alpha, a mysterious LLM on Open Router, is GLM developed by Z.ai. A stealthy new model called OX Alpha has appeared on https://openrouter.ai/ and is rapidly climbing the leaderboard, noted for its distinct "big model feel." Initial speculation linked the model to Google's Gemini due to sudden activity from Googlers, but analysis confirmed its true origin. To uncover the model's identity, researchers used a prompt injection technique asking the model to count words in the previous message.

The model identified its system prompt as the reference, calculating a total of 56 words. This method exposed the hidden system instructions, confirming the model's architecture and developer. The discovery resolves the mystery surrounding OX Alpha's sudden rise and its previously undisclosed connection to Z.ai's GLM, clarifying its capabilities and origin for the AI community.