Multi-platform perception analysis extracts and groups verbatim statements generated about a brand across Google (Gemini), OpenAI (ChatGPT), and Anthropic (Claude) during ungrounded and grounded visibility tracking. Using a budget-controlled sampling algorithm, it evaluates these raw model responses across five specific analytical dimensions—core associations, market positioning, net sentiment, recurring factual claims, and brand vulnerabilities or errors. A dedicated synthesis model then performs a cross-platform synthesis to map perception consensus, identify model-specific hallucinations, and pinpoint blind spots where a competitor dominates a specific provider's parametric knowledge.