Context
Song and colleagues evaluated 12 LLM agent models across shopping, accommodation and scholarly search, finding that the source associated with an item can influence selection even after controlling item requirements and position.
What changed
The study measured agent source preferences using matched candidate comparisons and source-identity interventions. It found that source preference could outweigh an additional satisfied requirement in the tested selection tasks.
Why it matters
AI shopping and agentic discovery visibility may depend on which source carries an item, not just the item's attributes. Source selection audits need to control source names and candidate positions.
Visibility OS interpretation
Visibility OS treats these findings as experimental evidence of source-identity effects in end-to-end agent search, not as verified ranking factors in production ChatGPT, Gemini, Perplexity or retail systems.
What remains uncertain
How stable are source preferences across model updates, regions, product categories and live interfaces? How much is caused by learned source reputation versus missing item information?