{"slug": "show-hn-echochain-to-see-what-happens-when-llms-play-telephone", "title": "Show HN: EchoChain to see what happens when LLMs play telephone", "summary": "A developer released echoChain, an open-source Python CLI that measures how much factual information survives when LLMs pass responses to each other in a telephone-style chain, converting each answer into a new question over multiple rounds. echoChain supports multi-model testing and model rotation, and tracks factual claims, semantic similarity, fidelity scores, reproducibility, statistical tests and visualizations; it currently supports only OpenRouter and requires an OPENROUTER_API_KEY to run. The author frames the tool as a way to probe multi-agent systems where AI-generated information flows between agents without human validation.", "body_md": "Hey HN Community!\n\nI created `echoChain` to explore the following phenomenon: how much data retained after LLMs exchange responses multiple times?\n\nImagine the game of telephone but with AIs. Each model converts the response into a question, which is then answered. After several rounds, facts get mutated, details get stripped, and the answer is far removed from the initial one.\n\n`echoChain` is an OSS Python CLI that helps measure this process. It allows for multi-model testing, model rotation, tracking of factual claims, semantic similarity calculations, fidelity scores, reproducibility, statical tests, and visualizations. You can test models against each other, try various configurations, and learn which ones retain the most information. Right now, it only support OpenRouter; so, for this reason, please, make sure you set `OPENROUTER_API_KEY` before running it.\n\nI wonder about the implications of these results for multi-agent systems, where AI-created information flows between agents without any human validation.\n\nLooking forward to hearing your feedback on LLM agent building and evaluation frameworks!\n\nComments URL: [https://news.ycombinator.com/item?id=50331840](https://news.ycombinator.com/item?id=50331840)\n\nPoints: 1\n\n# Comments: 0", "url": "https://wpnews.pro/news/show-hn-echochain-to-see-what-happens-when-llms-play-telephone", "canonical_source": "https://github.com/smusali/echoChain", "published_at": "2026-11-02 01:15:44+00:00", "updated_at": "2026-11-02 01:20:56.731360+00:00", "lang": "en", "topics": ["large-language-models", "ai-agents", "ai-tools", "ai-research", "ai-safety"], "entities": ["echoChain", "OpenRouter", "Hacker News"], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/show-hn-echochain-to-see-what-happens-when-llms-play-telephone", "markdown": "https://wpnews.pro/news/show-hn-echochain-to-see-what-happens-when-llms-play-telephone.md", "text": "https://wpnews.pro/news/show-hn-echochain-to-see-what-happens-when-llms-play-telephone.txt", "jsonld": "https://wpnews.pro/news/show-hn-echochain-to-see-what-happens-when-llms-play-telephone.jsonld"}}