Use for ontology-first planning, domain modeling, event modeling, ubiquitous-language clarification, architecture/design discussions with ambiguous terms, permissions/workflows/integrations/data-model decisions, or when the user asks for a conceptual model pass, system-language pass, term classification, or "explain the language first." Clarifies key terms, bounded context, ownership, lifecycle, relationships, domain-vs-implementation choices, and competency questions before recommending a decision.